The factors affecting apple transformation mediated by Agrobacterium tumefa-ciens had been studied through GUS transient expression. Such as different co-cultivation time, different bacterium density et al. Apple of Gala was transformed by Agrobacterium tumefaciens EHA105 earring LFY gene from Arabidopsis. It was proved by PCR analysis that the target LFY gene had been integrated into the genome of regenerated plants.