The purpose of this study was to investigate the effect of soaking seeds in water on their nutritional value. The seeds of kidney bean (Phaseolus vulgaris), soybean (Glycine max) and lentil (Lens culinaris) were investigated. Seeds were soaked for 1 day (24 h) or 2 days (48 h) in water at room temperature. The water was not changed. The samples before and after the soaking process were analysed for dry matter, crude protein, crude fat, crude fibre and crude ash contents. The water-soluble carbohydrates contents were calculated. The results obtained in this study showed that the soaking process of raw legumes seeds influenced their chemical composition. Negative correlations between crude protein and also crude fibre contents in the seeds and soaking times were noted. Contents of the other nutrients were correlated positively with the time of soaking.