An 18-year-old Pasadena, Md., woman was killed and eight other persons were injured yesterday afternoon when the woman's car collided head-on with a school bus near Gibson Island in Anne Arundel County, police officials reported.

They said Laura Marie Larson of 8402 Isles Dr. suffered head and other injuries in the accident, which occurred about 4:30 p.m., and died 2 1/2 hours later at University Hospital's shock trauma unit in Baltimore.

A passenger in the car, James Benjamin White III, 17, of Oxbury Road, Gibson Island, was listed in satisfactory condition last night at North Arundel Hospital with a head injury, according to hospital and police officials.

No one on the bus, which carried students at Cheseapeake High School, was seriously injured.

Police said Larson, who was taking White to his home on the Chesapeake Bay island, was driving her car south on Mountain Road (Rte. 177) about a mile west of Gibson Island when the car crossed the center line of the two-lane road and struck the northbound school bus head-on.

White is a student at Chesapeake High, police said, and Larson, who attended Anne Arundel Community College, graduated from Chesapeake last year.

Fifteen female students, returning to their homes after extracurricular activities at the school, were on the bus at the time of the collision, police said.

Seven of the bus passengers, ranging in age from 14 to 16, were also taken to North Arundel Hospital and were released after being treated for abrasions and contusions, police said. None of their names was available.

The bus driver, Pamela Sue Ruszin, 27, of Pasadena, was not injured in the accident, police said.