Tributyl phosphate (TBP) was evaluated for neurotoxicity in Sprague-Dawley rats (12/sex/dose group) treated daily by gavage in corn oil at dose levels of 0, 32.5, 100, or 325 mg/kg bw/day for 13 weeks. Motor activity tests and a functional observation battery (FOB) were conducted throughout the treatment period. At the completion of the study, neuropathological evaluation was performed on tissues (fixed by perfusion) of control and high- dose groups. Early deaths occurred in the mid- and high-dose groups, but the cause of death was apparently not compound- related. Clinical signs observed in the mid- and high-dose groups consisted of salivation, muzzle staining, urogenital/ventral surface staining, and alopecia. Body weight and body weight gain were significantly reduced (p < 0.05) in high-dose male and female rats. Food consumption was significantly reduced in high-dose males during the first week of treatment. Qualitative and quantitative FOB assessments (grip strength and hindlimb splay) did not reveal any significant effects that could be attributed to TBP-treatment. Results of motor activity tests and gross pathology evaluations were unremarkable. Microscopical examination of the brain (several areas), spinal cord (several levels), gastrocnemius muscle, and peripheral structures of the nervous system revealed no neurotoxic effects caused by treatment with TBP.