Hansenula anomala KCCM 11473, which grew well in Korean ginseng steaming effluent, was selected for the production of 5'-ribonucleotides. This strain had high RNA content. Optimal autolysis conditions were established to produce 5'-ribonucleotides (13.9similar to28.5 mg/g of biomass) at 55degreesC and pH 5.0 for 24 h. 5'-Phosphodiesterase and adenyl deaminase were not effective in increasing the yield of 5'-ribonucleotides, but the yield of IMP increased significantly only after the addition of 1.0% adenyl deaminase.