The application effect of different nitrogen form fertilizers on cotton is not clear. The effects of different nitrogen forms on cotton yield and nitrogen utilization were studied to provide a theoretical basis for efficient nitrogen application of cotton. Three different N fertilizer treatments(ammonium sulfate，urea and calcium nitrate)were set up with the application level of N 270 kg/hm². 15N tracer technique was used to study the effects of three different nitrogen forms on dry matter weight，seed cotton yield of single cotton plant，15N recovery，soil 15N residual rate and nitrogen loss rate of cotton under the planting mode of one film with three rows under drip irrigation under mulch. The results showed that there was no significant effect in dry matter weight of single plant between ammonium sulfate and urea treatments. In 2019，the dry matter weight of single plant for urea treatment was significantly higher by 5.6% than that of calcium nitrate treatment. There were no significant differences in the dry matter weight of single plant under the three different nitrogen forms in 2020. There was no significant difference in seed cotton yield of single plant between ammonium sulfate and urea treatments，which was significantly higher by 13.7% and 10.0% in 2019，and by 5.7% and 5.9% in 2020 than that of calcium nitrate treatment，respectively. The 15N recovery rates of ammonium sulfate and urea treatments were significantly higher than that of calcium nitrate treatment，by 1.1 and 1.6 percentage point in 2019 and by 6.4 and 3.5 percentage point in 2020，respectively. The 15N residual rate in soil for ammonium sulfate and urea treatment was significantly lower than that for calcium nitrate treatment，by 10.0 and 10.7 percentage point in 2019 and by 8.6 and 10.9 percentage point in 2020，respectively. The nitrogen loss rates of ammonium sulfate and urea treatments were significantly higher than that of calcium nitrate treatment in 2019，by 8.9 and 9.1 percentage point，respectively. The nitrogen loss rate of urea treatment was significantly higher than those of ammonium sulfate and calcium nitrate treatments in 2020，by 5.2 and 7.4 percentage point，respectively. In 2020，the content of nitrate nitrogen in 0～60 cm soil for calcium nitrate treatment at harvest stage was significantly higher than that for ammonium sulfate and urea treatments，and the content of nitrate nitrogen in 0～60 cm soil for ammonium sulfate was significantly higher than that for urea treatment. The results of two-year field experiment showed that under the conditions of one film and three rows planting mode and equal total nitrogen fertilizer application，compared with the application of calcium nitrate，ammonium sulfate and urea treatments had higher seed cotton yield，15N recovery rate and nitrogen fertilizer loss rate，and lower soil 15N residual rate and soil nitrate nitrogen content at harvest stage.