The aim of this study was to investigate the patulin concentration in apple juice commercialized produced in Mashhad city of Iran after treatment with So 2 and heat. Apple Juice samples were analyzed for patulin using reversed-phase high performance liquidated chromatography. The results of this study showed that temperature (90, 107.5 and 125°C for 30&268 min) and SO 2 (0&350 ppm) have significant effect on reducing patulin amount. The most effective condition in decreasing patulin was observed at 125°C and 350 ppm which resulted in about 86% reduction of patulin. Results showed that heat and SO 2 are the most effortless methods that be recommended for fruit juice industries in preventing infection which has got a major role in the product of patulin in apple juice.