Cryptococcus laurentii was tested as a biocontrol agent for reducing natural decay of arbutus berries caused by Penicillium citrinum and Verticicladiella abielina in semi-commercial postharvest trials. Three different preparations of C. laurentii were compared for antagonistic efficiency. Washed C. laurentii cells provided better protection against decay than yeast cultured in broth without washing while the culture supernatant free of yeast cells provided no protection. The protection provided by the washed yeast cells was dose-dependent. Cryptococcus laurentii was also effective in controlling decay at low temperature (4°C). The efficacy of C. laurentii was enhanced by the addition of 2% CaCl2. Agar disks of C. laurentii NYDA cultures placed on PDA plates seeded with pathogens did not inhibit the growth of P. citrinum or V. abielina. Spore germination of the pathogens in potato dextrose broth was strongly inhibited in the presence of active cell suspensions.