Transgenic tobacco plants have been regenerated from transformed callus tissues produced by the cocultivation of tobacco (Nicotiana tabacum L.) protoplasts with Agrobacterium tumefaciens C58. More than a half of regenerants exhibited normal-appearing vegetative morphology and produced progeny seeds(F1) by self-pollination. The F2 seeds were obtained from crosses between F1 plants and normal tobacco plants. Most of F1 and F2 plants appeared phenotypically normal. However, some of F1 and F2 plants showed hyperstyly flowers and remained sterile. Nopaline synthase (nos) gene sequence from transformed callus tissue was restricted by HpaII but nos genes of F1 and F2 plants were not restricted. Transcripts of isophethenyl transferase (ipt) and nos genes were detected from tumor callus tissues, but were not detected in normal-appearing F1 and F2 plants might be nethylated and be suppressed for transcription.