In this report, several factors such as infection time and concentration of bacterial suspension, influencing on transient gene expression in Agrobacterium-mediated transformation were evaluated. An appropriate concentration (O.D 600nm = 1.0-1.2) of bateria and 30 min of infection time showed a higher level of GUS expression. To improve transformation efficiency (TE), friable embryogenic calli (FEC) were bombarded by tungsten particles without plasmid DNA, and then co-cultivated with A. tumefaciens LBA4404 which contains pTOK233 super binary vector, carrying neomycin phosphotransferase (NPTII), hygromycin phosphotransferase (hpt) and$eta-glucuronidase$ (GUS) genes. Three days after co-cultivation with A. tumefaciens and particle bombardment, FEC cultures were transferred to the selection medium (SM: MS medium supplemented with BA 1mg/l, hygromycin 100mg/l, cefotaxime 250 mg/l and vancomycin 200mg/l). They were cultured for 2 weeks and then transferred to the second SM containing hygromycin 50mg/l, cefotaxime 200 mg/l and vancomycin 100mg/l. Later, stable GUS expression was detected 4 to 6 weeks after transfer to the SM. Further, TE from Agrobacterium-mediated transformation after particle bombardment increased to about 3-folds compared with Agrobacterium-mediated transformation without particle bombardment. In the present study, we established an efficient transformation protocol of zoysiagrass by using A. tumefaciens in the combination with particle bombardment for the first time.