Two playwrights and five theater groups were presented with cash awards by The Village Voice as off-Broadway honored its own with the 30th Anniversary Obie Awards.

The $1,000 Obie prize for best new play went Monday to Maria Irene Fornes for "The Conduct of Life." Meredith Monk received the other $1,000 prize for sustained achievement.

Obies for distinguished playwriting were awarded to Christopher Durang for "The Marriage of Bette and Boo"; William Hoffman for "As Is"; and Rosalyn Drexler for "Transients Welcome."

Cash grants of $2,500, awarded by The Voice to "theater groups who have maintained a high level of quality while working under budget restrictions," went to Intar, the Production Company and the Richard Allen Center. Spiderwoman Theatre and the Split Britches Company each received $1,250.

Other kudos: John Lithgow and Rosemary Harris won Drama Desk Awards for best actor and actress. Lithgow portrayed an over-the-hill fighter in "Requiem for a Heavyweight," and Harris won for "Pack of Lies."

In a third awards ceremony, "Ma Rainey's Black Bottom" by August Wilson was named Monday as the best play of the 1984-85 theater season by the New York Drama Critics' Circle.