Abstract: The effect of 2 strains AM fungi（GM Glomus mossea-2，GV Glomus versiforme）inoculation on the yield and nutrient quality of 8 different muskmelon varieties were studied under protected cultivation. The results showed that most varieties muskmelon seedlings inoculated with AM fungi grew better than ordinary seedlings，especially in photosynthetic rate and root activity. The single fruit weight of GM inoculation plants might grow bigger than non-mycorrhizal ordinary plants，so the yield of AM muskmelon was increased. The nitrate and nitrite content in AM fruit were significantly decreased than control fruit，but the content of soluble solids，total sugar and vitamin C in AM fruit became higher than control fruit，so the nutrient quality of muskmelon were improved by AM Fungi inoculation. From the root AM fungi colonization ratio between GM and GV，the GM is screened to be the best AM fungi strains to inoculate muskmelon，and the suitable host muskmelon varieties are Fenglei and Zhongmi 5.

Key words: muskmelon, variety, AM fungi, organic soil substrate, yield, nutrient quality