The division and differentiation of protoplast isolated from leaf mesophyll tissue of four cultivars of Lycopersicon esculentum and L. pimpinellifolium were investigated. When protoplasts were cultured on the MS medium modified by the elimination of NH4NH3 and the addition of 1000mg/l myo-inositol 100mg/l L-glutamine, plating efficiency of 58% in cultivar Boksu#2 and 62% in L. pinpinellifolium were achieved by using the protoplasts isolated from in vitro grown and 3-week-old plants. All the callusea tested turned green on the MS medium containing 10μM IAA and 10 μMBAP, or 10μM IAA and 0.5μM seatin. but shoots were only differentiated from the protoclone callus of L. pinpnellifolium.