The effect of hyperbaric treatment (between 0.3 and 0.9 MPa)at 20◦C on antioxidants and antioxidant activity was evaluated in comparison to atmospheric pressure at 20◦C and the commercial storage temperature (13◦C). The lycopene content of hyperbaric treated tomato fruit was noticeably inhibited during the treatment where as its accumulation was enhanced during ripening compared to untreated fruit (20◦C control). In general, hyperbaric treatment did not appreciably influence ascorbic acid and total phenolic content of tomato fruit. However, hyperbaric pressure at 0.9 MPa induced the accumulation of significantly higher amounts of bothascorbic acid and total phenolic content in tomato compared to the 13◦C treatment. Antioxidant activity determination showedthat even though lycopene content was significantly affected bytime and treatment conditions, no significant difference in LAA was encountered. The trend of HAA was in accordance with the result son ascorbic acid and total phenolic content. Generally, the HAA increased as time progressed and did not noticeably differ among treatment conditions. However , after ripening, it is likely that the hyperbaric pressure at 0.9 MPa caused a significantly higher HAA compared to 0.1 MPa at 13◦C. Overall, hyperbaric treatment at 20◦Chas potential to extend tomato shelf-life during short treatment durations without adverse impact on quality during ripening. More study is required to determine optimal pressures and treatment times to produce the highest quality.