Maurice B. Mitchell, the former chairman of the board of National Public Radio, could potentially earn a $173,000 profit on a $100 investment in the company that plans to buy NPR's share of a satellite information distribution network, according to the company's audited financial records.

Mitchell stands to make the profit if the company, National Information Utility Corp. of McLean, succeeds in selling its stock to the public at a planned price of $7.50 a share.

Mitchell was chairman of NPR in June, 1982 when the public radio network signed an agreement with NIU to develop the satellite data system.

After stepping down as NPR chairman last July, Mitchell became a consultant to NIU and a member of the board. In April 7, 1983, he bought 23,078 shares of NIU stock from the privately held company for a total of $100 or less than half a penny a share, reports filed with the Securities and Exchange Commission show.

Now, as part of a plan to raise $5.5 million to help NPR by buying out its interest in the venture, NIU is planning to sell stock to the public. At $7.50 a share, Mitchell's investment would be worth $173,085, or 1,700 times what he paid for it.

Mitchell yesterday described the potential profit projection as "unrealistic" and denied any irregularities or conflict of interest in his dealings with NIU and NPR.

Noting that the SEC has not yet approved public sale of the NIU shares, he said, "you can't sell that stock, its worthless.

"You're using numbers that I think are unrealistic" he said.

"If you see some impropriety, that's ridiculous," said Mitchell, now director of the Washington Program in Communication Policy Studies of the Annenberg Foundation. "To say there is some impropriety in this reverses the facts."

Mitchell said he had no financial interest in NIU while serving as chairman of NPR and was not involved in the original decision to form a partnership of the two ventures. As chairman of NPR's board of directors, he said, he presided over board meetings but did not vote except to break deadlocks.

"If I had been a director of NIU at that time, I could see the conflict, but I wasn't," he said.

Mitchell said he acted as an intermediary between NIU and NPR and passed on the offer to buy NPR's share of the satellite data system. The offer depends on NIU succesfully selling stock to the public, which would create a market for the shares owned by Mitchell.

Mitchell was one of several NPR officials quoted in June, 1982 as enthusiastically endorsing the formation of INC Telecommunications, a partnership owned 80 percent by NIU and 20 percent by NPR.

"This new partnership signals a timely advance in the transmission of digital data and computer software," he said in a press release at the time. The joint venture, he proclaimed "will ensure revenue both from INC and local sources when it is urgently needed."

The partnership was to use NPR's satellite network and the FM radio transmitters of public radio stations to distribute computerized information.

Before the satellite data network could get off the ground, NPR ran into serious financial problems and last week announced plans to sell its interest in the system to NIU for $5.5 million.

Though NPR officials said they expect to get the badly needed cash by September, The Washington Post disclosed yesterday that NIU financial statements show the company had only $3,627 in the bank as of March l and is itself in precarious financial condition.

NIU "has no substantial assets, no customer contracts and no immediate sources of revenues" the financial reports say.

The financial problems are so serious, warned NIU's auditors Arthur Andersen & Co., that "the company may not be able to continue in existence."

NIU hopes to solve its own financial problems and raise the $5.5 million needed to buy out NPR by selling stock to the public.

The offering statement filed with the SEC says NIU has about 5.8 million shares of stock, most of them issued to insiders who paid a fraction of a penny a share for it. NIU founder Jack Taub and his brother, Bert, control more than 3 million shares, for which they paid $20,000.

The SEC report lists Mitchell as the owner of some 23,000 shares for which he paid $100. Mitchell said he was uncertain whether he had paid for the shares. "Technically I don't think I've paid for it."

Mitchell said that a few months after leaving NPR, Taub asked him to become a consultant to the satellite data venture and to serve on its board of directors. Mitchell said he has advised the firm on plans to beam information to school systems but the board has never held a meeting.

A former president of Encyclopaedia Brittanica, Mitchell said he has not been paid as a consultant because "I didn't want to be paid, I didn't need the money." Instead, he agreed to accept stock, a practice he described as common among companies just getting off the ground.