In agricultural production, nitrification inhibitors and microbial agents are often used as fertilizer synergist to coordinate soil nutrients and promote crop growth. In order to solve the problem of nitrogen utilization in facility melon production, two kinds of nitrification inhibitors, 3,4—dimethylpyrazole phosphate (DMPP) and dicyandiamide (DCD), and microbial agent were selected as test materials to study the effects of their single application or combination of inhibitors and microbial agent on melon growth and soil nitrogen utilization through a field experiment. The results showed that the addition of nitrification inhibitors and microbial agents could promote melon’s growth. During the growth period of melon, the application of synergist regulated the supply state of soil nitrogen and reduced the pH of rhizosphere soil. Among all treatments, C+DMPP+J treatment had the most significantly positive effect on melon growth and soil nitrogen utilization. Compared with conventional fertilization treatment, C+DMPP+J led to that melon production was increased by 21.7%;during the growth period, the plant height and stem diameter were increased by 13.6% (40 days after transplanting) and 8.9% (65 days after transplanting) at most, and the ammonium nitrogen was increased by 96.9% (90 days after transplanting, 20—40 cm), the nitrate nitrogen in soil decreased. It significantly improved the partial productivity of nitrogen fertilizer (21.6%), agronomic efficiency of nitrogen fertilizer (60.7%) and physiological utilization rate of nitrogen fertilizer (40.3%).The combination of nitrification inhibitor and microbial bacteria agent with chemical fertilizer showed obvious inhibition effect on soil nitrogen transformation, the content of ammonium nitrogen was higher during the growth period of melon, which extended the supply time of soil nitrogen. It could be seen that nitrification inhibitors and microbial agents combined with chemical fertilizers could prolong the nitrogen release cycle, which should be of great significance for reducing nitrogen loss and increasing crop yield.