Two hundred paintings of Filipino masters, all accessioned at the UST Museum of Arts and Sciences, were surveyed to determine their state of preservation. Forty-three (21.5%) oil paintings were found to be in different states of deterioration with mold attack as the most common cause. Fungal infestations were most evident on pigments, wood support and paper backing. The infested paintings, based on the records at the museum, are between 50 and 100 years old. Infesting molds were isolated by swab method and purified through a series of transfer in plates of Malt extract agar (MEA) with pH 3.5 and incubation temperature of 280C. Forty-eight isolates in six genera as follows were obtained and identified based on cultural and morphological characteristics in MEA: Aspergillus and Penicillium (Deuteromycota); Rhizopus, Mucor and Cunninghamella (Zygomycota); and Chaetomium (Ascomycota). Aspergillus is the most prevalent with 77% occurrence in all the paintings sampled. It is followed by Penicillium, 13%, and then Chaetomium sp., 4%. The lesser isolates wherein each has an occurrence rate of 2% are Mucor, Cunninghammella, and Rhizopus.

Key words: Fungi, infesting, oil painting, and museum of arts and sciences.