From 2019 to 2021, the types and quantities of weeds in Chongzhou, Meishan and Mianyang in the Chengdu plain were investigated using the five-point sampling method. In response to dominant weeds, the plant protection unmanned aerial vehicle (UAV) control experiments were also performed in direct seeding rice fields of Chongzhou, including UAV with IDK-015 nozzle plus Maifei adjuvant treatment (the tested group) and conventional UAV spray treatment (the control group). The deposition of spray mist on the upper, middle and lower layers were collected by using Mylar sheets and photo paper. The results of the three-year survey showed that the main weeds in the direct seeded rice fields in Chengdu Plain belonged to 13 families and 24 populations. Among them, the relative probabilities were all greater than 20% for Echinochloa crusgalli, Cyperus difformis, Leptochloa chinensis, Eclipta prostrata and Alternanthera philoxeroides , which were dominant weeds. UAV spray test results showed that the pesticide liquid deposition per unit area (0.23 μL/cm2) and the effective pesticide liquid deposition rate (50.30%) of the tested group were significantly higher than those of the control group (0.14 μL/cm2，42.53%). After spraying 30 days, the control effect and fresh weight control effect of the tested group on Echinochloa crusgalli, Eclipta prostrata and C. difformis were all above 94%, which were higher than those of the control group.