Harvard players surged into the semifinals last night on three of the four teams remaining in competition for the Mixed Doubles title in the National Indoor Women's Tennis Tournament at the Longwood Courts in Newton.

Today will see Paul Sullivan, a top Crimson competitor last year, and his sister Jeanne a Leslie College graduate, in one semifinal match, while Ted Weld is the Harvard half of a second team facing Chauncey Steels and Miss Carol Wright, singles winner of the 1960 Tournament.

The Sullivans will play the winners of a third-round contest which was still in progress early this morning. The brother sister team pulled out a 7-5, 7-5 victory over a pair of Providence players a few minutes before midnight.

Weld's team reached the latest round by defeating Carrie Heldman and Frank Ripley at 6-3, 7-5 yesterday. The losers had earlier taken a two-out-of-three decision from a pair that included Gary Adelman: Mike Belknap and Allen Terrell were also eliminated in other play. Wright and Steel qualified by beating Janet Christenson and Jim Gustafson.

The tournament finals will follow tomorrow for today's winners. Miss Wright is the only champion of an earlier tournament to return for this year's play.