Determination of 9 kinds of herbicides containing nitrogen in agricultural products was studied by GC and HPLC. FTD-GC and UV-HPLC methods were compared for adaptability, sensitivity of the pesticides, and for interfering peaks from food components. Swep (N-phenylcarbamate), diuron, linuron (urea type) and propyzamide (acid amide type) were decomposed during determination by GC. Alachlor and butachlor were not able to be determined by HPLC. Sensitivities of the pesticides by GC were 5 times (50 times by the same injection volume) that by HPLC, and GC was more sustainable for in terfering peaks than HPLC. Preparation method for test solution was systematically established according to the kind of agricultural products. Pesticides in common vegetables and fruits were directly determined for the extracts, and recoveries of the pesticides added at 1 ppm were 77.1-96.5%. Extracts from onion, garlic, etc. were purified on a florisil column before determination, and recoveries of the pesticides added at 1 ppm were 77.2-89.7%. Extracts from grains, beans, etc. were defatted by coagulation, purified on a florisil column before determination, and recoveries of the pesticides added at 1 ppm were 77.5-89.6%.