The development of a new analytic method for the extraction and determination of the biopesticide present azadirachtin in real samples of fish and in samples of water of fish ponds, it allows the injection of the fish extracts and water of the pomds, in a column cromatographic ISRP-C18 (250mm x 2mm DI), without previous treatment of the sample. The recoveries of azadirachtin in fortified fish samples were higher than 90% with inferior standard deviation at 14.6%. The detection limits and quantification for the azadirachtin were of 0.02 and 0.12µgL-1, respectively. In 86% of the 42 samples of fish azadirachtin masses among 0.14 to 2.317µgL-1 was detected.

KEY WORDS: HPLC; Azadirachtin; fish; biopesticides