In order to determine whether the gustatory system can be modified by restricting dietary NaCl during early development, neurophysiological taste responses were recorded in rats at various times after deprivation, and behavioral taste preferences were measured in adults. Rats deprived of dietary NaCl from the third day of gestation to 12 days postnatally and then placed on a NaCl-replete diet had chorda tympani nerve responses similar to those of nondeprived rats when recordings were made at 28 days of age and older; however, preferences for NaCl solutions over water were significantly less than those of controls when tested at adulthood. NaCl deprivation in pups from the third day of gestation to approximately 35 days postnatally resulted in altered chorda tympani nerve responses to NaCl but not to other stimuli such as NH4Cl and KCl. Therefore, restriction of dietary NaCl at a period in the rat's development when peripheral and central taste responses are changing results in short-term alterations in peripheral neural responses and in long-term changes in preference behaviors.