Garlic (Allium sativum L.) is one of the most important bulb crops. Allicin was proved as the most important composition which has been used for human, animal and plants to fight against kinds of diseases. So, the allicin content was the most important quality trait for garlic. An efficient UPLC method for determination of allicin in garlic bulb were developed and used to detect the allicin content among 212 accessions of garlic germplasm. In the UPLC method，methanol/water (50︰50, v/v) as a mobile phase which ran through at a constant flow rate of 0.3 ml/min was performed on UPLCTM BEH C18 column. Allicin content of 212 accessions of garlic were determined by the UPLC.The content of allcin among the germplasm was significantly different. The highest content is 3.01% which was almost four times of the lowest content of 0.82%.