Abstract: Two kinds of haptens, CBRH Ⅰ and CBRH Ⅱ,for carbaryl had been synthesized and covalently conjugated to bovine serum (BSA), human serumin albumin (HSA) or ovalbumin (OVA) to prepare synthetic antigens (immunogens) and coating antigens. The polyclonal antibody which is specific to carbaryl was obtained from New Zealand white rabbit's sera by using the CBRH Ⅰ BSA as immunogen. The hapten and antibody were tagged by horseradish peroxidase and three fomats of enzyme linked immunosorbent assays (ELISA) were established for the determination of carbaryl. With the optimized format and the conditions of ELISA, the detection limit was lower than 0.01ng/ml,and there were no interference caused by other common used carbamate insecticides.