In order to establish an immunoaffinity column-HPLC method for aflatoxins (AFs) in cocoa powder and cocoa, anti-AFB1 monoclonal antibody (AF.2) was bound to Affi-Gel 10 gel (16 mg/ml), and the antibody-binding gel was packed into a mini column. Cocoa powder (10 g) spiked AFs were extracted with 50 ml of acetonitrile : water (60+40). The extact were 10-fold diluted with PBS and cleaned-up by the IAC. These recoveries of 1 and 3 ng of AFs/g were 72.3～102.0% and RSD were 3.3～6.6%. But when 10 ng AFs/g were added, these recoveries were 62.9～70.7% and RSD were 6.7～22.3%. Cocoa (10 g) spiked 6 ng of AFs/g were extracted with 50 ml of acetonitrile : water : methanol (60+40+20). The extact were 20-fold diluted with PBS and cleaned-up by the IAC. These recoveries of AFB1 and B2 were 73.4 and 82.3% and RSD were 5.5 and 3.4%, respectively. But these recoveries of AFG1 and G2 were less than 45% and RSD were about 9%. Three cocoa powder and 13 cocoa samples on the market were analyzed in this method. All cocoa powder samples were contaminated 0.40～0.94 ng of AFs/g. One cocoa samples were 0.1 ng of AFG1/g.