In this research, two environmentally compatible compounds namely Acetone and Carbon dioxide were evaluated for their efficacy against of Tribolium castaneum (Herbst), under laboratory conditions. The LC25 and LC50 values of Acetone and Carbon dioxide were estimated on adult insects. Furthermore, LC25 and LC50 values for Acetone and Carbon dioxide treatments on adult insect were 9.84 and 23.24 μ l L-1, 11.08 and 19.21 mg L-1¬, respectively. After determining the LC50 and LC25 values of two agents, to evaluate the combined effects of Acetone and Carbon dioxide an experiment was conducted in the form of completely randomized design with four treatments including LC50 (Ac), LC50 (Co2), LC25 (Ac) plus LC25 (Co2), and control. Our results demonstrated that Carbon dioxide was more effective. The results showed that percentage mortality combination two environmentally compatible compounds treatments on adult insect in 24, 48 and 72 h were 36.6, 66.6 and 90 percent compared with Acetone (16.6, 33.33 and 50) and Carbon dioxide (20, 36.6 and 53.33) alone and control have significant differences (P<0.05).The results showed that the combination of Acetone and Carbon dioxide have good additive effect when compared with applied individually treatments against of one important stored product pest.