Former congressman Otto Passman was acquitted today of charges that he accepted illegal gratuities from South Korean rice dealer Tongsun Park and evaded paying income tax on the money. He also was acquitted of a conspiracy charge.

The jury deliberated only 90 minutes this afternoon after hearing closing arguments. When the verdict was announced, the 78-year-old Passman - who had wept at times during the day's earlier proceedings - leaped up and embraced his lawyer.

Passman was chairman of a House Appropriations subcommittee at a time when Park sought help from Congress in promoting sales of American rice to South Korea.

Today's closing arguments painted conflicting portraits of Passman, with the prosecution describing him as motivated by greed in the Korean bribery scandal and the defense calling him the victim of a conspiracy.

The government relied heavily on Tongsun Park and his records during the three weeks of testimony here in an effort to prove its charges of conspiracy, acceptance of illegal gratuities and tax evasion.

In his forceful presentation today, Justice Department attorney Morris See PASSMAN, A22, Col. 1 PASSMAN, From A1 Silverstein told jurors: "Don't let any April Fool's jokes be played on you" by the defense; "Otto Passman wanted his share of the spoils." Silverstein told them also not to be confused by defense attorney Camille F. Grael Jr.'s cross-examination of Park-"Tongsun Park is not on trial here."

Silverstein warned the jurors not to be swayed by Passman's service as a congressman to his district.He told the jurors, all past constituents of Passman, that he was motivated by "plain greed."

The government's closing argument dwelled on letters the-Rep. Passman wrote for Park to Korean officials and on payments Park allegedly made to Passman.

Park testified that most of his payments to Passman were delivered in cash to the congressman in his Washington office. Passman has continually denied receiving any money from Park.

In his impassioned closing steatement, defense attorney Gravel said Passman "answered America's call to greatness" when he entered Congress in 1946.

"Otto Passman," Gravel told the jury, "was an unknowing victim of an evil Korean conspiracy" and the government's case against Passman was "a house of straw built on a foundation of gummy rice laced with the gravy ot Tongsun Park."

Thoughout the trial Gravel tried to discredit Park and his testimony. Today he acknowledged it was "true that Park was not on trial," but that Park's truth and veracity were. Park was motivated, Gravel said, by a "sinister effort to involve a man defeated in 1976 and who could not help or hurt him anymore."

Gravel contended Park testified only after the government provided for his immuity and in an effort to extricate himself from his tax problems.