Ketoprofen-antioxidant mutual prodrugs were synthesized to reduce the gastrointestinal effects associated with ketoprofen. For reducing the gastrointestinal toxicity, the free carboxylic group (-COOH) was temporarily masked by esterification with alcoholic/ phenolic -OH of natural antioxidants thymol, guaiacol, menthol and vanillin. In order to obtain the derivatives with improved in vivo lability, the double ester prodrugs i.e. ketoprofen-antioxidant through the glycolic acid spacer (-CH2COO-) have been synthesized. These mutual prodrugs were evaluated for their anti-inflammatory, analgesic and antiulcer properties. The results indicate that there is merit to extend the therapeutic utility of this potential NSAID by developing the ketoprofen-antioxidant mutual prodrugs as gastroprotective NSAIDs.