Fourteen-year-old Marian Sison of Arlington eliminated three-time champion Jane Mack of Richmond, 4 and 3, in the first round of the 61st Virginia Women's Amateur golf championship today.

Sison, a 100-pound golfer who just completed the eighth grade, used a string of two pars and a bogey on holes four through six for a 3-up lead and stayed in front.

Defending champion Donna Andrews of Lynchburg beat 1975 winner Nancy Hollenbeck of Alexandria, 7 and 5. Brenda Seymour of Chantilly advanced over Peggy Yountz of Virginia Beach, 9 and 7, as the field was reduced to eight.

U.S. Women's Amateur: Tina Barrett of Baltimore, runner-up in the recent Maryland Women's Amateur, shot 72 yesterday at Columbia Country Club to lead six qualifiers for the national event.

Other qualifiers for the Aug. 11-16 tournament in Santa Cruz, Calif., were Kathy Quelland of Ocean City, Md., 74; Maryland Women's champion Sarah LeBrun of Baltimore, Bonnie Fry of Maryland Golf and Country Club, and Lois Ledbetter of Rockville, at 75, and Lori Van Sickle of Wilmington, Del., 77. Kim Williams of Potomac, runner-up in last year's U.S. Amateur, is an automatic qualifier.

Maryland State Junior: Kim Cayce of Potomac shot 83 for a 36-hole total of 160 to win the girls division of the Maryland State Junior tournament at Rolling Road in Catonsville. Alan Myers of Severna Park won two matches and gained today's boys semifinals.