Using unfertilized ovaries of pumpkin as explants, we determined the effect of different combinations and concentrations of growth regulators, genotypes, embryo sac development stages, disinfection methods and duration of high-temperature pretreatments on embryoid induction via in vitro culture to establish a regeneration system of unfertilized ovaries of pumpkin.The media MS + 4.0 mgL-1 2, 4-D + 0.5 mg L-1 NAA + 1.0 mgL-1 6-BA and MS + 0.04 mgL-1 TDZ achieved higher induction rates, 19.8% and 20.1%, respectively, as compared to other media examined, with the TDZ-induced method easier to operate.Among the 6 pumpkin varieties tested, two (Xue feng mi ben and E yu nan gua), with stronger growth,had higher embryoid induction rates and were more suitable to be used as experiment materials.The operation of slicing and then sterilizing the ovaries picked on bloom day decreased the cavernous callus formation effectively and increased the embryoid induction rate.Treatments with darkness and heat shock (35℃) for 5 days could help ovaries turn green and induce embryoids.When moved to hormone-free MS medium, the cotyledon embryos developed to regenerated seedlings and survived after transplantation.Seven regenerated plantlets had chromosome number n=x=22 and an average number of chloroplasts in stomatal guard cells of 4.28, so they were haploid plants.