Abstract: It is a long-term task for modern agriculture to develop innovative fertilizer and enhance the use efficiency of mineral nutrients. Granular fertilizer was made by mixing maize straw biochar produced at different temperatures with NPK mineral fertilizers. A field test on moisture soil was set up in order to investigate the effects of biochar-complex fertilizer on the yields and nitrate content of the cabbage and radish. The results showed that the biochar complex fertilizer could significantly enhance the concentrations of soil available P and K by 14%- 61% and 3%- 29% respectively, compared with common chemical complex fertilizer. The fresh biomass of Brassica chinensis had an increase of 21%-93%. The contents of N and K in the cabbage were lifted by 3%-64% and 39%-41% respectively. The fresh biomass of Raphanus sativus var. radculus was increased by 20%- 45% . But the concentrations of NPK were similar in the radish of all the treatments (P>0.05). The nitrate concentration of the fresh biomass was significantly higher in both vegetables under the treatment of 500℃biocar-complex fertilizer. Fortunately, the nitrate concentration was far below the limit of direct eligible vegetable and didn’t decrease the quality of these two vegetables. Generally, the biochar produced at high temperature had much stronger impacts on soil and plants.