Abstract: In order to clarify the status of pesticide residues in watermelon fruits produced by different cultivation methods and their differences, this paper took 65 watermelon samples produced in three cultivation methods: Large shed, small arch shed, and open field as the research object, and 60 pesticide residues in the completed samples. On the basis of quantitative analysis, through technical methods such as chronic and acute dietary risk analysis and risk ranking, the differences of pesticide residues in watermelon fruits produced by the three planting methods were discussed. The results showed that: Some samples had residual pesticides, but their chronic and acute dietary risks were not high; among the three planting methods, the open field planting method had the largest number of residual pesticides, with 9 types, and the proportion of very lowrisk samples was also low. In the other two methods, it reached 76%; in addition, the three types of planting methods need to focus on the relatively high risk of different types of residual pesticides. The green house used triazophos, and the small arch house used difenoconazole, profenofos, and chlorofluoro cyanurate. Pyrethrin was grown in the open as triazophos, profenofos, and prochloraz. Based on the above analysis, it could be concluded that among the three planting methods, the risk of pesticide residues in watermelon grown in open field was relatively high, and supervision should be strengthened according to the differences in the types of pesticide residues with relatively high risks.