High embryogenic calli of three cutivars of Kentucky bluegrass, Md, Bd, and Gm, were in-duced from mature embryos, and were proliferated on medium K3 and K5. Embryogenic calli were trans-formed with plamids pDM803 and pBY520 by microprojectile bombardment. Fourty-two transgenic lines hadbeen obtained. The highest efficiency of transformation reached to 3.7 % for cv. Md, 2.8 % for cv. Gm, and5 % for cv. Bd. The micro nutriment of Cupric had significant effect on transformation. The embryogenic cal-lus cultured in dim-light condition had higher transformation efficiency than the green callus cultured in lightcondition for one month before transformation. The selective regime and selective pressure on the putativetransgenic plants were important for obtaining the desire number of transgenic plants. It also affected the copynumber of integrated genes in the genomic DNA of transgenic plants.