Mary Treadwell, former director of a real estate spinoff of Youth Pride Inc., was indicted yesterday along with an accountant and three officers of the organization on charges of stealing and misappropriating thousands of dollars from the federally funded low-income housing projects they managed.

A federal grand jury charged in a 30-count indictment that Treadwell and the others portrayed the spinoff, P.I. Properties, to government officials as a charitable, nonprofit business, but actually used it illegally to fund their own profit-making enterprises and to pay personal expenses.

The grand jury alleged that the five were involved in a conspiracy that destroyed and altered financial books and records, filed false reports with the government, laundered money through various businesses and bank accounts and then obstructed the access of government officials to financial data.

The indictment alleges that security deposits from low-income tenants at Clifton Terrace Apartments and Kenesaw Apartments in Northwest and the Buena Vista Terrace Apartments in Southeast Washington were used improperly as collateral for bank loans in the name of P.I. Properties. The indictment said money from those loans was funneled into profit-making enterprises in which four of the five were involved.

In addition, operating funds from Clifton Terrace were diverted to finance renovation work on private homes, to decorate the office of an advertising firm, to make down payments on real estate for other profit-making enterprises and to pay personal legal fees, according to the indictment.

In the summer of 1977, the grand jury alleged, Treadwell and the accountant, Ronald S. Williams, used $3,500 in operating funds from Clifton Terrace toward payment for wedding and engagement rings they bought from a New York jeweler. The two were later married.

Treadwell, 40, and Williams, 38, were charged by the grand jury with conspiracy to defraud the government through false statements, mail fraud and wire fraud.

Also charged with the same offenses were:

* Joan M. Booth, 37, who is Treadwell's sister and who served as resident manager of Clifton Terrace;

* Robert E. Lee, 37, who was a general manager of P.I. Properties; and

* Charles W. Rinker Jr., 41, who as an official of P.I. Properties handled some of the administrative work carried out at the Youth Pride headquarters and 16th and U streets NW.

The grand jury indictment also charged Treadwell with three counts of tax evasion for her alleged failure to pay more than $52,000 in income taxes owed from 1976 to 1978.

Booth is also charged with one count of tax evasion, for understating her income in 1976 by about $15,000 and failing to pay taxes on the extra money. Lee was also charged with understating his income by about $33,000 in 1976 and with not paying taxes on those additional earnings.

Treadwell cofounded Youth Pride in 1967 along with Marion Barry, whom she later married and who is now mayor. None of the allegations presented by the grand jury yesterday, which concerned events that occurred between 1974 and 1978, involved Barry, who was never an official of P.I. Properties. Barry and Treadwell were divorced in 1977. The mayor has said that he severed all links with Youth Pride and its affiliates in 1978.

Barry, who testified before the grand jury, made only a brief comment yesterday, telling reporters at the District Building, "The grand jury action speaks for itself. It would be inappropriate for me to say anything else about it."

Rinker said yesterday, "I am not guilty of any of the charges they have brought against me." Rinker, who now runs a financial consulting business that advises tenants who want to buy buildings targeted for condominium conversion, said, "I believe I'll be vindicated in the long run . . . It's going to be hell for me and my family in the process."

None of the others indicted could be reached for comment yesterday.

Youth Pride, the longest living of more than a dozen Pride affiliated organizations, closed its doors last August.

The grand jury investigation began in October 1979 after a series of articles in The Washington Post detailed a complex scheme in which Treadwell, Booth and Lee allegedly stole, diverted or misapproriated at least $600,000 from the U.S. government and low-income tenants at the 285-unit Clifton Terrace complex at 14th and Clifton streets NW.

The Post accounts were based on interviews with hundreds of tenants and current and former associates and employes of Treadwell, including 200 hours of interviews with Zellene Laney, the P.I. Properties bookkeeper during that period of time.

While yesterday's indictment capped an unusually long, 2 1/2-year probe and roughly coincided with the end of the term of the current grand jury, U.S. Attorney Stanley S. Harris said in a press release yesterday that the investigation of Pride would continue. Harris did not elaborate on the statement.

The 32-page indictment handed up in U.S. District Court yesterday does not state a specific total amount of money allegedly stolen or misappropriated. Instead, it chronicles 50 acts that were allegedly part of a complex web of secret, insider deals in which thousands of dollars intended for some of the city's worst housing projects were siphoned off by principals tied to what was once one of the formemost self-help groups in the city.

The indictment alleges that the defendants used P.I. Properties, which had tax-exempt, nonprofit business status, to acquire Clifton Terrace from the Department of Housing and Urban Development in July 1975, and also to misappropriate, steal and divert funds from Buena Vista Terrace Apartments on Shipley Terrace SE and the Kenesaw Apartments at 3060 16th St. NW.

The Buena Vista complex was owned by Youth Pride Economic Enterprises Inc., a profit-making enterprise, and managed by P.I. Properties. The Kenesaw Apartments were owned by the Antioch School of Law and were managed for a year by P.I. Properties.

In order to acquire Clifton Terrace and maintain its tax-exempt status, the grand jury alleged, the defendants falsely told the IRS that P.I. Properties was a nonprofit organization, that none of its earnings would benefit any of its employes or directors and that any other businesses controlled by the defendants "were unrelated to those envisoned for P.I. Properties."

The indictment alleges, for example, that in July 1975 Rinker applied for a $5,000 loan from the Riggs National Bank in the name of P.I. Properties, but the money actually was used by Treadwell for personal expenses.

A year later, Treadwell, Lee, Booth and Rinker obtained another loan from Riggs for $25,000, again in the name of P.I. Properties. Of that money, $5,000 was deposited into an account for Pride Economic Enterprises Housing and Real Estate, a profit-making business involved in landscaping, maintenance and management of rental properties, according to the indictment.

In August 1976, the four P.I. Properties officers negotiated a $25,000 loan from National Savings and Trust Co., again in the company's name, using as collateral Clifton Terrace and Buena Vista security deposit and tax escrow funds. The proceeds of that loan went into an account of Pride Environmental Services Inc., a profit-making business involved in the sale of advertising space on trash cans.

In September 1976, the grand jury alleged, Lee and Booth took $5,500 from Clifton Terrace and Kenesaw accounts to reimburse T. Barry Associates for purchase of property in Southeast Washington. T. Barry Associates was a profit-making business involved in advertising and public relations.

The following November, the grand jury alleged, Treadwell, Lee, Booth and Rinker got a $19,000 loan from National Savings and Trust--again using the name of P.I. Properties and using as collateral security deposit accounts from Clifton Terrace, Buena Vista and Kenesaw as well as a P.I. Properties tax escrow account.

Of that loan, $8,956.09 was used toward a purchase of property on Swann Street NW by Sticks and Stones Inc., a profit-making organization involved in property purchase and renovation.

According to the indictment, Treadwell was a director or chief executive officer of the profit-making organizations that the grand jury alleges received money misappropriated and stolen from the housing projects managed by P.I. Properties.

Lee and Booth were also officers or employes of Sticks and Stones and Pride Economic Enterprises Special Police, a profit-making organization that provided security guard service.

In addition to his duties with P.I. Properties, Rinker was an officer of Youth Pride, Pride Economic Enterprises, the special police, Pride Environmental Services, T. Barry Associates and its division known as Kiosk Advertising, which sold ads to be placed on the trash cans owned by PES, according to the grand jury indictment.

The indictment alleges that in November 1976, Treadwell, Lee, Booth and Ronald Williams altered, destroyed and hid various business and financial records from Clifton Terrace.

Treadwell and Williams were married in September 1977. The previous July 27, Treadwell put a $500 deposit on engagement and wedding rings at Friman and Stein Inc., a New York jeweler, and three days later, she paid $554 in Clifton Terrace operating funds to Williams, the grand jury indictment said. The next day, Williams sent a check for $500 to Treadwell, the grand jury said.

A month later, Treadwell wired $3,500 in Clifton Terrace operating funds to Williams' bank account in Plainfield, N.J., the indictment said. According to the grand jury, Williams withdrew $3,300 from the account and used $2,050 to pay the balance on the engagement and wedding rings.

The grand jury investigation that led to yesterday's indictments was supevised by Assistant U.S. Attorneys William D. Pease and Stephen R. Spivack working with investigators from the FBI, the IRS and the inspector general's office of the U.S. Department of Housing and Urban Development.

The conspiracy charge against each defendant carries a penalty of five years in jail, a $10,000 fine or both. Each defendant is also charged with 16 counts of making false statements to either the Department of Housing and Urban Development or the Internal Revenue Service, which carries the same penalty. All five defendants are also charged with mail fraud and wire fraud, each of which is punishable by a five-year jail term or a $1,000 fine or both. The penalty for tax evasion is five years in jail, a $10,000 fine or both plus the cost of bringing the prosecution.