Gram-positive bacteria, Bacillus subtilis BR151 and Staphylococcus aureus RN4220 were transformed with high efficiency by electroporation. The cells were incubated until late log phase, washed three times with 10% glycerol, 1mM HEPES, 12% sucrose and resuspended to $10^{10}{sim}10^{11}cfu/ml$, then stored at -$70^{circ}C$. Transformation efficiency of B. subtilis BR151 was $1.03{ imes}10^7cfu/{mu}g$ with cells washed with 10% glycerol and electroporated by 15KV/cm, 0.7msec pulse with pUB110. Transformation efficiency of S. aureus RN4220 was $4{ imes}10^6cfu/{mu}g$ with cells washed with 1mM HEPES + 10% glycerol and electroporated by 15KV/cm, 2.5msec pulse. The number of total transformants was 1000 when B. subtilis BRI51 was transformed with 100ng pUB110 DNA and the number of total transformants was 9000 when S. aureus RN4220 was transformed with 10ng pUB110 DNA