Abstract: ObjectiveThe study were carried out to investigate growth and developmental regulation of intracavity seeds in muskmelon,and provide reference for improving seed production yield and quality.MethodThe experiments used inbred line 05-6 whose seeds germinated in fruit as material. Seeds growth and development in fruit after pollination, occurrence time and change trend of intracavity seeds germination were analyzed. Differences of seeds plumpness,germi-nated seed number,germination rate, survival seedlings rate,robustness level of seedlings in different days after pollina-tion were compared.ResultThe maturity of intracavity seeds was earlier than muskmelon fruits. On day 26 after pollina-tion,seeds were fully matured. In terms of the ungerminated seeds, compared with seeds on day 35 after pollination(when the fruit were completely mature),there were no significant(P>0.05)differences in seeds plumpness,number, germination ability,survival seedlings ability,robustness level of seedling. By contrary,the number of germinated seeds was signifi-cantly fewer than that in fruit on 35 d after pollination(P<0.05).ConclusionPicking up fruit and collecting seeds in ad-vance before fruits is matured fully is effective strategy for reducing seeds germination rate in fruit,and the most suitable picking time was day 26 after pollination for muskmelon 05-6.