Acetosyringone, which is one of the phenolic compounds produced by wounding plant tissues, actively induces the transfer of T-DNA from Agrobacterium to plant. To produce transgenic calli from tea plant (Camellia sinensis), leaf explants of the tea plant were co-cultivated with Agrobacterium tumefaciens LBA4404 harboring pB1121 under different acetosyringone concentration conditions. After the infection, these explants were placed on a medium containing 200 mg/L kanamycin and then resistant calli were selected. Although callus differentiation was not observed without acetosyringone at 10 μM application, resistant calli were obtained from the explants treated with acetosyringone. In particular, the application of 500 μM of acetosyringone promoted the production of resistant calli. When the fluorogenic assay was carried out to detect the GUS gene expression, one resistant callus showed the activation. In addition, PCR and PCR Southern blot analyses confirmed that the resistant calli were transformants.