Large numbers of viable mesophyll protoplasts are isolated from soil-grown plants of Pinellia ternata Breit of Araceae by liquid-solid double layer media with different concentrations of mineral salts, hormones and sugar. The first division of protoplasts takes place in 4—7 days of culture, with a division frequency of 3—8%. Cell clusters of 80—100 cells form in 3 weeks. They are transferred into a liquid medium to culture for a month on a shaker to form calli of 1—2 mm diameter which are transferred onto a solid differentiation agar medium. The calli first proliferate and grow, and differentiate into green buds and small seedlings in 3—4 weeks. The plantlets of Pinellia ternata regenerated from protoplasts grow to a length of 6—10 em in another month. It was found that the shoot-forming process in the calli was to proceed in two ways: one was the organogenesis way, and the other was the embryoid way. Comparisons were made between the effects obtained from the 3 different methods, i.e. component c Large numbers of viable mesophyll protoplasts are isolated from soil-grown plants of Pinellia ternata Breit of Araceae by liquid-solid double layer media with different concentrations of mineral salts, hormones and sugar. The first division of protoplasts takes place in 4-7 days of culture, with a division frequency of 3-8%. They are into a liquid medium to culture for a month on a shaker to form calli of 1-2 mm diameter which are The calli first proliferate and grow, and differentiate into green buds and small seedlings in 3-4 weeks. The plantlets of Pinellia ternata regenerated from protoplasts grow to a length of 6-10 em in another month. It was found that the shoot-forming process in the calli was to to proceed in two ways: one was the organogenesis way, and the other was the embryoid way. ethods, i.e. component c