The purpose of the experiment is the development the optimal condition of chemical material by liquid chromatography-tandem mass spectrometry. Determination of chemical material residues in supplementary diets, hard clam and the soils of hard clam farm by liquid chromatography-tandem mass spectrometry. Study on accumulation and metabolism in hard clam with supplementary diets and chemical material. The chloramphenicol, sulfonamide, nitrofuran metabolism， malachite green and Leucomalachite green of the limit of detections(LODs) are 0.1ppb,5ppb,0.5ppb and 5ppb in hard clam tissue. The linear correlation coefficient r2 are larger than 0.99 .The test divided into four groups, one is control group, the others are 1,3,5 ppm groups. The maximum Sulfadimethoxine concentration in 1,3,5 ppm groups are 48 hour,48 hour and 18 hour. The Sulfadimethoxine residues in hard clam tissue fell below the detection limit of 5 ppb on the 18th day.