Abstract: Using the pot experiments, the study of the effect of Urea-ammonium chloride mixed treatments on the nitrate content in Brassica campestris L. ssp. chinensis var. utilis Tsenet Lee was carried on, the results are as follows:With the increase of use of ammonium chloride, The Cl- content in Brassica campestris L. ssp. chinensis var. utilis Tsenet Lee increase obviously; and nitrate content reduce obviously, but the total N, total chlorophyll content and yield befor harvest don, t vary evidently.