This study was aimed at the effects of ozonation and conventional pasteurization process on chemical properties, antioxidant activity, phenolic substances, and sugar composition of apple juice. Microbial and chemical properties analyses were carried out. Determination of phenolic substances and sugar profile analysis in apple juice samples was performed using High-Performance Liquid Chromatography; ORAC, TEAC, and total phenolics assays were also included. The ozone treatment of the apple juice was effective for both decreasing the total viable microorganisms and maintaining the quality characteristics of apple juice. The ozone treatment decreased total mesophilic bacteria in apple juice. The heat treatment resulted in a reduction of the chlorogenic acid content whereas ozone treatment had no significant effect. It has been determined that the application of ozonation in apple juice is equivalent to pasteurization.