The Denver Intl. Film Festival will file for protection under Chapter 11 of the Federal Bankruptcy Act following the decision of the board of the Denver Film Society.

Despite years of chipping away at accumulated debts, the Society now faces indebtedness of about $140,000.

The 1990 festival cost about $350,000, and receipts for that festival, in which 20 of the 90 programs offered were sellouts, totaled $103,100, with 17,000 to 18,000 in attendance. In 1988 the festival went into the black, but accelerating costs have now voided that.

The Society also faces a suit for $33,000 filed by the weekly newspaper Westword over support provided for the 1988 and 1989 fests, an arrangement concluded in 1990 when the Cherry Creek Shopping Center, where the festival was held, became the principal sponsor.

The debt figure of $140,000 includes about $80,000 from the 1990 festival but does not include the $33,000 being claimed by Westword.

The Society plans a fundraising effort to keep the 14-year-old fest alive; $50,000 must be raised within 30 days in order for the 1991 fest to take place.

The total cumulative deficit consists of $70,000 in unsecured liabilities, $60,000 in a five-year secured bank loan, the $33,000 contested Westword liability, and monthly overhead, which will be reduced from $15,000 to $7,000.

The festival will move to donated office space by June 1.