•Immersion of contaminated pistachio nut in citric acid solution and then ozonation plus UV-C exposure could be used to degrade aflatoxins in nuts.•The UV-C, had more effect on AFB2 and AFG2.•The O3 treatment degrades AFB1 and AFG1 more than AFB2 and AFG2.•Acid treatment had more effect on AFB1 and AFG1, against AFB2 and AFG2. The effects of gaseous ozone (O3), UV-C radiation, and citric acid (CA) on aflatoxins degradation in contaminated pistachio samples were investigated. By the evaluation of different combinations, the optimum amounts of O3, UV-C, and CA were achieved. The best treatment was a combination of the immersion of the samples in 3 N CA, 30 minutes’ exposure to O3, and 36 hours exposed to UV-C radiation, by this combination more than 90 % of aflatoxin B1 and aflatoxin B2 and more than 99 % of aflatoxin G1 and aflatoxin G2 were degraded. No significant changes were observed in total fat content, protein content, acid and peroxide content, total phenolic compounds, soluble and insoluble carbohydrates of pistachios. Also there were no significant changes between sweetness, acidity, flavor, color, and overall quality of treated and non-treated samples. The results showed that the combination of O3, UV-C, and CA was much more effective than the effect of each of them alone.