Abstract: In this work the effect of ozone treatment during post-harvest period on thedevelopment of fungi, yeasts and bacteria present on the surface of strawberry fruit cv. Candongawas investigated. Moreover the effect of ozone treatment on strawberries shelf life was evaluatedusing McKinney index. Ozone was applied in air at 5ppm for 24h, or in water at 0.8ppm for2min, strawberries were conserved in ventilate or in a passive refrigeration chamber. The aim ofthe work was to investigate if ozone can control the development of the microorganisms presenton the surface of the considered fruits in order to extend their shelf life. The results show thatozone treatment plays a control effect on microorganism contamination and increases shelf life.