Only 24 hours after he was issued a court summons upon being accused by a security guard of shoplifting a $16 item from a Charlottesville, Va., department store, University of Virginia basketball star Olden Polynice yesterday announced he will pass up his senior year of eligibility and turn professional.

Polynice's decision ends a three-year college career that was a mix of sometimes superb basketball and occasional bouts with trouble.

According to Charlottesville Chief of Police John Dekoven Bowen, Polynice was detained Wednesday by a security guard at Rose's Department Store in the Barrack's Road Shopping Center after allegedly taking an undisclosed item. Bowen confirmed last night that Polynice signed a summons on the spot to appear in court on May 30, when he will face a charge of larceny misdemeanor.

Polynice and Virginia Coach Terry Holland made no mention of the incident yesterday in taped interviews with the school's sports information department. Both, however, referred to Polynice's off-court problems as being part of the reason he decided to leave school.

In November 1984 he was cleared by a student committee of a charge of violating the school's honor code, but he admitted he turned in another student's English paper as his own. And in a late-season practice skirmish this year, the 6-11 Polynice broke the nose of teammate John Dyslin, which reportedly upset several Virginia players.

" . . . I wanted to stay here badly . . . a lot of things have been bothering me, and those things have caused me to finally sit down and decide what would be best for me. . . . I've got to move on. I figured going pro would be the best thing for me to do," Polynice said in the taped interview.

His voice was very subdued during the two-minute talk. And Holland added: "I think there are some outside influences other than just the basketball end of it that have bothered Olden that were certainly factors in his decision.

"Again, he has dealt the last two years with some pretty tough situations . . . "

Polynice, from New York City and Port-au-Prince, Haiti, led Virginia in scoring and rebounding in each of the past two seasons. After averaging 16 points and eight rebounds per game this past season as a junior, he was voted second-team all-Atlantic Coast Conference and was named honorable mention all-America by the Associated Press.

Next season, Polynice figured to be the best center in the ACC, and Virginia stood to be one of the league's best teams because every player has eligibility remaining.

It is unclear just how highly the NBA scouts regard Polynice. In a draft where Chris Washburn from North Carolina State appears to be the only top pro pivot prospect, it's not inconceivable that Polynice could be one of the top seven "lottery" picks in the NBA draft.

Holland said yesterday that Polynice was "obviously distracted" in recent weeks. And although he supposedly was not in academic trouble, the situation "affected him academically," Holland said, adding that Polynice seemed "very bothered by the decision. . . . It was hard for him to tell me he was leaving."

Holland said Polynice's departure "means back to the drawing board" for Virginia's 1986-87 season.

And it means basically the same thing for Polynice, who three years ago promised his family he would graduate.

"I was on schedule to graduate," Polynice said. "I need 30 hours to graduate. . . . I'm not going to break that promise to them. I'm just going to concentrate on my finals and finish up the year, academically, on a positive note."