The use of edible plants for the production and delivery of vaccine proteins could provide an economical alternative to fermentation systems. The construction of the plant expression vector pBI121-A was reported, which contained a fusion gene encoding hepatitis A capsid proteins. The gene was located between the left and right Ti border sequences under the control of CaMV35S promoter. The vector was identified via PCR and restriction enzyme analysis and was introduced into Agrobacterium tumerifacience LBA4404. The transgenic Citrus plants were produced by Agrobacterium-mediated transformation of epicotyl segments.13 putatively transformed plants through the kanamycin selection were micrografted onto the seedlings. The presence and integration of the transgene had been verified by PCR analysis. The result showed that five transformants were integrated and the transformation efficiency was 4.1%.