Three methods of chromosomal counting of the root, morphological identification and chloroplasts counting of stomatal guard cell were used to identify the ploidy of 46 regenerated plants from unfertilized ovary pumpkin. The results showed that 12 regenerated plants were poor growth, thinner leaf, unobvious vein, fewer branches, undeveloped root system and significant differences in morphology compared to the others; only 7 regenerated plants were found that the chromosomal number was n=x=22 by chromosomal counting of the root; the average number of chloroplasts in stomatal guard cell was 4.28 for the seven haploid regeneration plants, while the normal tissue cultured seedling was 8.37. The results suggest that morphological identification is an auxiliary mean for ploidy identifications and chromosomal counting is a direct, accurate but inefficient method, chloroplasts counting in stomatal guard cell is easier and more effective.