This study was carried out to investigate possible trichloroacetic acid (TCA) effects on the activity of glucose 6-phosphate dehydrogenase (G6PD) and carbonic anhydrase (CA) in muscle and liver tissues of rats under laboratory conditions. Five Sprague-Dawley albino rats were used for experiments, and 200 mg TCA/kg body weight was administered intraperitoneally. Tissue G6PD and CA activities in muscle and liver of rats were determined six hours after treatment. According to the results, the TCA treatment caused significant decrease in muscle and liver G6PD, but no significant difference in liver CA level was observed, in comparison to control rats. Therefore, it is conceivable that TCA is a toxicant like other pesticides, and is primarily interacting with liver and muscle tissue cells.