Wheat, a staple food in Egypt, is severely damaged by insect pests, particularly the red flour beetle, Tribolium castaneum (Herbst), when stored in bulk quantities. The current study was conducted to determine the efficacy of ECO₂-Fume fumigant (mixture of phosphine and carbon dioxide gases) and Ozone on T. castaneum different stages. The ECO₂-Fume fumigant was treated at concentrations of 30, 35, 40, and 50 g/m³, with exposure for three days. Mortalities increased with increasing concentration and exposure period. After three days of application ECO₂-Fume gas the mortality rate was 80.06, 85.6, 76.7, and 82.2% for eggs, larvae, pupae, and adults, respectively when applied at a rate of 40 g/m³. The mortality rate was 100% for previous stages respectively when applied at a rate of 50 g/m³. Application of Ozone gas in this experiment were 500 ppm for at ten different exposure times of 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 hours. The mortality percentage increased gradually by increasing the exposure time after treatment. The LT₅₀ and LT₉₀ to Ozone gas against T. castaneum larvae to 500 ppm were 0.07, and 1.75 days; and it was 0.19 and 6.22 days for adult. Therefore, the use of ECO₂-Fume fumigant and Ozone gas is a very important alternative method to protect stored grains and their products against T. castaneum.