As shown in Fig.3, the contents of malondialdenyed in all samples increased during storage. The malondialdenyed contents of the green bell peppers treated with 5,10, and 20 mg L-' chlorine dioxide were not significantly (P > 0.05) different. No significant difference (f0.05) was found in the malondialdenyed contents between the samples treated with 50 mg L-I chlorine dioxide, and the control. However, it was significantly higher (PO.05) than those of other treated samples during the last stage of preservation, which indicated that the 50 mg L-' chlorine dioxide gas treatment could lead to malondialdenyed accumulation in green bell peppers during preservation.