Abstract: Specific and hignly sensitive enzyme-linked immunosorbent assay(ELISA) was applied to identification of pregnacy bloodstains using monoclonal antibodies against the carboxylterminal portion of β-subunit. When experimentally prepared bloodstains(about 30 μl blood)were submitted to analysis, OD values in Pregnaoy Bloodstains is 0.39+0.16; OD value in nopregnacy bloodstains is 0.03±0.06. The reaction did not chang significantly when these bloodstains were stored at room temperture for three months. After three months HCG confers in pregnacy bloodstains decreased with increacing aged bloodstains. The HCG cotents can be detected in pregnacy bloodstains exposed to the sun for two months.