Abstract: The limited mobility of phosphorus (P) in soil is a critical factor constraining P use efficiency. To explore the effects of different P fertilizer drip application methods on the spatial distribution of soil P availability, a study was conducted to compare drip and basal fertilization on soil P supply, cotton yield, and P utilization efficiency. The findings provided a basis for improving the utilization efficiency of P fertilizer. A five-year field experiment (2018—2022) was conducted in the 144th Regiment of Shihabi City, Xinjiang, China. Six fertilization treatments were established: no P fertilizer (CK), broadcast application of triple superphosphate (TSP-B), monoammonium phosphate (MAP-B), ammonium polyphosphate (APP-B), 20% broadcast + 80% drip application of monoammonium phosphate (MAP-D), and 20% broadcast + 80% drip application of ammonium polyphosphate (APP-D). The P application rate was 43.7 kg/hm2. Soil available P content was monitored annually, and cotton biomass, yield, and aboveground P uptake were measured. The effects of basal and drip application of P fertilizer on soil P supply, crop yield and P use efficiency were analyzed. The results showed that: 1) MAP-D and APP-D treatments significantly increased the available P content in the 0～5 cm soil layer. Compared to base application, APP-D increased available P by 104% over APP-B, and MAP-D increased it by 110%. In the 0～20 cm layer, the average available P content under APP-D and MAP-D was significantly higher than that of their basal application counterparts. APP-D also exhibited significantly higher available P than MAP-B and TSP-B in 0～20 cm soil layer. 2) Drip application of P fertilizer significantly improved P use efficiency in cotton compared to basal application. APP-D achieved the highest P use efficiency (52.76%). The shoot P uptake in APP-D was significantly higher than that in APP-B and MAP-D. 3) During the boll opening period in 2022, the cotton biomass treated with ammonium polyphosphate was significantly higher than that of other treatments. From 2018 to 2022, the cotton yield under monoammonium phosphate drip treatment was significantly higher than that under no phosphate fertilizer or triple superphosphate basal application. In 2018 and 2022, the yield of drip MAP was higher than that of basal MAP treatment. Long-term P application increased the Olsen-P content in cotton field soil. Drip application significantly enhanced Olsen-P in the topsoil, with the greatest increase in available P observed in the surface soil layer. The utilization rate of drip application P fertilizer was consistently higher than that of base application. This study provides a theoretical basis for improving the P fertilizer efficiency under integrated water and fertilizer management.