Abstract: In order to speed up the popularization and application of plug seedling production technique of pumpkin, the suitable seedling substrate was screen out to provide practical basis for the field production and planting of Jianbao pumpkin. By using two kinds of commercial substrates commonly used in Fujian Province and three kinds of formula substrates prepared with vermiculite, peaty soil and pearl rock as the raw materials, the effects of different seedling substrates on the seedling growth of Jianbao pumpkin. The results showed that different seedling substrates had great influence on various morphological indexes of Jianbao pumpkin seedlings. When the seedling age was 18 days, the strong seedling index treated with D Xinfeng agricultural substrates was 31% higher than that of the compared garden soil (CK), and the G value was 41% higher than that of the compared garden soil (CK). The plant height, stem diameter, strong seedling index and G value of pumpkin seedlings treated with D Xinfeng agricultural substrate were significantly higher than those treated with other treatments. The seedlings were strong and grow well, which could fully meet the seedling growth of pumpkin, and were suitable for the popularization and application as the seedling substrate for the cultivation of Jianbao pumpkin.