A study was conducted to find out the possibility of utilizing cucurbit seeds as food resources of fats and proteins. The pumpkin and melon seeds contained about 41% of crude fat and about 31% of crude protein. The lipid fractions obtained by silicic acid column chromatography were mainly composed of about 96% neutral lipid, and among the neutral lipid separated by thin layer chromatography, triglyceride and free fatty and were major components in both seeds. The predominant fatty acids of the pumpkin and melon seeds were linoleic acid(51.8∼70.5%), palmitic acid(11.0∼27.8%) and oleic acid(7.8∼16.4%). The salt soluble proteins of the cucurbit seeds were highly dispersible in 0.02M sodium phosphate buffer containing about 1.0M MgSO₄ salt, and the extractabilities of the pumpkin and melon seed proteins were 40% and 32%, respectively. Glutamic acid, arginine and tyrosine were the major amino acids, and the essential amino acids such as lysine, threonine, valine, methionine, isoleucine, leucine and phenylalanine were detected in both seeds. The electrophoretic analysis showed 6 bands in pumpkin seed protein and 8 bands in melon seed, and the collection rate of the main protein fractions purified by sephadex G-100 and G-200 were 58.3% in pumpkin seed and 55.0% in melon seed. Arginine and glutamic acid were the major amino acids in the main seed proteins and the molecular weight for the ruin proteins of the pumpkin and melon seeds were estimated to be 48,000 and 78,000, respectively.