Baltimore Colts quarterback Art Schlichter, in seclusion in Columbus, Ohio, after aiding the FBI in a gambling investigation, said through his lawyer yesterday that he never bet on Colt games last year.

Under terms of the National Football League constitution, a player can be fined, suspended or banned for life for gambling, at the discretion of Commissioner Pete Rozelle. The commissioner also could take no action.

The NFL said yesterday it is investigating alleged gambling by Schlichter, which the FBI said resulted in a debt of $389,000, and that a league representative had talked to him. It was the NFL's first acknowledgment that Schlichter, a Baltimore rookie last season, is the unnamed player cited in court records who went to the FBI in March after gamblers had allegedly threatened to tell the Colts about his gambling.

Ernie Accorsi, the Colts' general manager, said in a statement that he had spoken with Schlichter (who for a time, sources said, was in the FBI's protective custody) to express the team's "interest and concern for his welfare and to urge his cooperation with both federal authorities and the NFL office."

Jack Chester, a Columbus attorney who represents Schlichter, described his client as "a material witness" involved in the prosecution of four Maryland men indicted Thursday on gambling charges by a federal grand jury in Columbus.

Three of those men were arrested in Columbus after traveling there, allegedly to receive payment for some of Schlichter's debts. According to court records, those three were Samuel R. Alascia of Catonsville, Md., and Harold E. Brooks Jr. and Joseph Serio of Baltimore. Charles T. Swift of Baltimore was arrested in Baltimore. Court records said that the unnamed person who cooperated with the FBI, now identified as Schlichter, will not be charged for any of his gambling activities.

Speaking for Schlichter, Chester said that "none of the charges involve any football game in which Mr. Schlichter, or any team of which he was a member, participated."

According to league sources, most, if not all, of Schlichter's betting involved basketball games, played from January to March of this year.

According to an FBI affidavit filed with the courts, Schlichter paid off $230,000 between January and March after two of the four men named in the indictement traveled to Columbus. Included in the $230,000 was a $60,000 payment that reflected $50,000 in debts and $10,000 in interest. The affidavit said that from March 1 to March 8, Schlichter lost another $159,000. He told the FBI that he was being charged $10,000 a week in interest on that debt.

The bets were made from a telephone in Columbus to the bookmakers in Baltimore, according to the affidavit. Schlichter, whose family lives in Bloomingburg, Ohio, attended Ohio State University, which is located in Columbus.

According to the FBI, Schlichter approached agents at the Columbus bureau March 15, telling them he was engaged in illegal betting. The FBI said it confirmed, by monitoring phone calls, that two men known to Schlichter as "Sammy and Sid" threatened to go to the Colts if Schlichter did not pay off his debts.

Schlichter then apparently cooperated with the FBI in a plan to apprehend the gamblers. In subsequent phone calls between Schlichter and "Sammy and Sid," an FBI undercover agent was introduced to the two men as someone who would bankroll Schlichter so that he could pay his debts. According to the affidavit, a settlement was reached to reduce the debt to $149,000, to be paid off in three installments from April 1 to April 15.

The FBI said the first meeting was to take place at Port Columbus International Airport at 10:15 a.m. last Friday, April 1. "Sid" allegedly told the undercover agent to make a payment of $65,000, all of it to be in $50 and $100 bills and to be placed in a briefcase. The affidavit said that on April 1 the FBI observed Brooks, Serio and Swift boarding a flight in Baltimore and flying to Columbus. At the Columbus airport, the affidavit said, Brooks met with the FBI undercover agent to pick up the $65,000.

Schlichter was signed by the Colts last year to a multiyear contract that included a $350,000 signing bonus and a $145,000 salary in 1982. He was the Colts' first-round draft choice after an all-America career at Ohio State.

He was beaten in the preseason for the Colts' starting quarterback job by another rookie, Mike Pagel. Schlichter wound up playing in only three games, and did not start in any. He completed 17 of 37 passes for 197 yards and no touchdowns. He had two passes intercepted.

According to a report in the Columbus Dispatch, the Columbus Organized Crime Bureau investigated Schlichter's gambling habits while he was attending Ohio State in 1980. The newspaper quoted sources as saying that the bureau considered questioning him, but did not do so because Ohio State campus police and school athletic authorities would not cooperate.