This study was conducted to examine the effect of chronic low dose organic solvent exposures in the industries towards then neurobehavioral functions of workers subjective symptoms on neurobehavioral function as well as a visual reaction time test (Flicker test) were administered to 94 exposed and 162 unexposed workers in a oil refinery and some other auto-repair shops. The results obtained were as follows: 1. Symptom complaints were higher and Flicker test values were lower in exposed workers than in unexposed workers. 2. Flicker values were inversely correlated with urinary Hippuric acid concentration in exposed workers (r=-0.26, p<0.05). 3. Flicker values were inversely correlated with subjective symptom score (r=-0.15, p<0.05). Low Flicker value were also related with some subjective symptoms such as "Dimmed vision", "Nightmare", "weakness on extremity" in workers as a whole. While symptoms of "Dimmed vision", "Nightmare" only observed among exposed workers.