An approach for ammonia synthesis by using an air-reduced iron powder-water system through discharge under normal temperature and normal pressure is designed and preliminarily established by means of experiments. In this system, with air as the nitrogen source and water as the hydrogen source, fixation of nitrogen to ammonia is realized through discharge in the presence of reduced iron powder. It is confirmed by the experiments, the reduced iron powder has significant promoting effect on the fixation of nitrogen to ammonia. It is proved by the study the n(NH4+)/n(NO3-) ratio in the product is relevant to the increase of the duration of discharge. This study has important value and significance to the continuous development of basic research of ammonia synthesis and innovation in experiment teaching.