The effect of induction and differentiation of callus was studied with the cotyledon and hypocotyl of tomato in different kinds and concentration of antibiotics, and the effect of antibiotics on inhibiting Agrobacterium was also analyzed after infecting explants in tomato. Results indicated that the ideal selecting pressure of kanamycin was 50 mg·L-1 in cotyledon and 40 mg·L-1 in hypocotyls when kanamycin was used as selection marker. In the experiment of inhibiting Agrobacterium there were no significant differences between cefotaxime and carbenicillin. The negative effect of cefotaxime was more effective than that of carbenicillin. Therefore, the ideal antibiotics was carbenicillin and its ideal concentration was 350 mg·L-1 in tomato transformation.