Culture conditions were studied for plant regeneration from mesophyll protoplasts of Solanum toxicarium. Axenic seedlings of S. taxicarium were used as material for protoplast culture. Many viable protoplasts were isolated by incubating leaf slices in an enzyme solution containing 0.25% Meicerase and 0.05% Macerozyme for 16 hours at 25℃ without shaking. Protoplast density of 5.0×10^4·ml^<-1> in 1/2 MS media containing 0.1mg·liter^<-1> NAA and 0.1mg·liter^<-1> kinetin was suitable for colony formation. Most colonies were formed when protoplasts were cultured at 25℃ for 2 weekes after initial culture at 30℃ for 3 weeks. On the MS agar medium with 5mg·liter^<-1> zeatin, 34.9% of protoplast-derived calli differentiated shoots. These shoots rooted on 1/3 MS medium with 5g·liter^<-1> sucrose and 0.7% agar, and developed into whole plants.