Maryland Del. Sheila Hixson was slightly injured early yesterday in a three-car accident involving a police cruiser chasing three teen-agers in an allegedly stolen automobile.

Hixson's car was struck by the fleeing auto as she was returning home from a Montgomery County delegation meeting on raising the county's drinking age from 18 to 19. Authorities said the 17-year-old driver of the sedan, who faces auto theft and "numerous traffic charges," was not intoxicated at the time of the incident.

Police spokesman Phil Caswell said the allegedly stolen car, a late-model Lincoln Mark IV, led police on a high-speed chase up and down Rockville Pike. The black luxury sedan, operating without lights, evaded a police barricade and was traveling north on Rockville Pike when it struck Hixson's car in the middle of the intersection with Maryland Rte. 28, Caswell said. One of two pursuing police cars then struck the Lincoln.

Hixson, 38, was treated for cuts and bruises and released from Shady Grove Adventist Hospital. Her son said she was resting at home yesterday. The officer in the first patrol car, William Peterson, sustained head injuries and a possible concussion but was also treated and released from the same hospital.

Police said the two passengers in the Lincoln, a 16-year-old youth and Frank Charles Clinton, 19, of Washington also were charged with auto theft.