Controversial landlord Shao Ti Hsu, the millionaire engineering professor who owns hundreds of low-rent apartments in the Washington area, was hospitalized briefly for a facial injury last night after an incident at one of his apartment developments.

Hsu, 63, was treated at Leland Memorial Hospital in Riverdale for a wound over his right eye.

Questioned by a reporter as he left the hospital wearing a bandage over his eye, Hsu said only, "nothing happened."

Hyattsville city police said they were investigating and that the principals in the incident told different versions of what happened. The police would not say what the conflicting stories were.

Several tenants of the Emerson Garden apartment complex at 4300 Emerson St., Hyattsville, said the incident occurred when Hsu, who owns the project, saw Dave DeChant, who works with a community organization, talking to a group of tenants.

They said DeChant, of the Neighborhoods Uniting Project, was discussing a meeting at which he was to talk to the tenants last night when Hsu ordered him to leave.

An argument broke out between the two men, witnesses said. During an ensuing struggle, DeChant was squirted in the face with a chemical disabling spray and Hsu was hit on the head with a 3 1/2-foot yellow metal pole wrapped with black tape that Hsu had been carrying, witnesses said.

Hsu, a professor at the University of Maryland has been a center of controversy. In 1976, District housing officials named him the single most frequent violator of the city's housing code. The FBI is investigating allegations that Hsu and former Sen. Vance Hartke (D-Ind.) offered a Prince George's County housing official $4,000 a month to keep the county from interfering in their efforts to buy and operate several run-down housing projects.