A cross-sectional study was performed to evaluate the effects of chronic exposure to solvent on neurobehavioral performance of solvent exposed 89 workers engaged in a video tape manufacturing fatory. A control group of 43 workers was selected fro different sections of the factory. The mean age and the mean duration of employment were 29 years and 5.4 years. Each workers completed a medical and occupational questionnaire. Adverse effects on the central nervous system were assessed by self reported Scandinavian questionnaire 16, New Anxiety-Depression Scale and seven test of Swedish Performance Evaluation System. These included simple reaction time, choice reaction time, digit classification, finger tapping speed, additions, symbol digit and digit span. Several potential confounding factors were included as indepedent variables in all analysis of neurobehavioral tests and symptoms. These included age, sex, educational level, familiarity with computer, alcohol drinking and amount of smoking. No significant associations were found between solvent exposure and total symptom score and mood score, Although the mean duration of employment was 5.4 years, comparison of mean performance scores adjusted for confounding factors showed a significantly poorer performance on choice reaction time(p<0.05), digit classification (p<0.01), additions (p<0.01) and symbol digit(p<0.01) in exposed group. Factor matrix of neurobehavioral tests produced by varimax rotation showed three distinct factors, which correspond to assessments of "memory", "coordination" and "response speed". These factors accounted for 62.6% of the total variance of the sample. Familiarity with computer was found to be associated with performance of symbol digit and amount of smoking appeared to slow finger tapping speed. Male and college graduate workers have less errors than others. There were no significant correlation between neurotoxic symptom score and performance of neurobehavioral tests.