Abstract: The paper aims to study the effects of different fruit thinning methods on dry matter, yield and quality of melon simplified cultivated in uncovered field. In the condition of simplified cultivation, took ‘Huangpi 9818’as the experimental material, the author set three treatments as each plant with two fruits, three fruits and arbitrary bear fruit, made a comparative analysis of dry matter amount difference, fruit characteristics and yield and quality in maturation stage. The results showed that there were some differences of dry matter amount, fruit characteristic and yield quality among three fruit thinning methods. Amounts of dry matter accumulation in each treatment presented as T3 (887.1 g/plant)＞ T2 (860.2 g/plant)＞ T1 (771.2 g/plant), and T2, T3 reached the significant difference with T1, refraction sugar content of T1 was higher than that of T2, T3 in two harvesting periods. To integrate high-yield characteristics and economic benefits, treatment of arbitrary bear fruit (T3) has high yield to 31200 kg/hm², and the economic benefits is 62400 yuan/hm².