Lawrence S. DiCara '71, president of the Boston City Council, yesterday announced his candidacy for Massachusetts state treasurer. DiCara plans to run against incumbent Robert Q. Crane in the Democratic primary in September.

DiCara said yesterday he is running for treasurer "because the inefficient and archaic practices of the current administration have cost the people of this state tens of millions of dollars."

Five Harvard undergraduates are working on the campaign: Mark Roosevelt '79, campaign manager; Jonathan H. Alter '79, press secretary; Dewitt C. Jones '79, issues adviser; Pierce Cray '79, finance committee member; and Peter Slavin '79, field coordinator.

Slavin, who met DiCara in 1976, said he was impressed with him and volunteered to be his field coordinator for the fifth, sixth and seventh congressional districts. Slavin said yesterday that politics is a "fun game to play but its too much of a game to make a career out of."

DiCara holds degrees from Suffolk Law School and the Kennedy School of Government. He has worked recently with the Robert F. Kennedy Action Corps community projects.