Catalytic combustion of acetaldehyde has been investigated as a representative of unpleasant odor by its reaction with metal-phthalocyanines(PC). The experiment was conducted at the reaction temperature of 200~41$0^{circ}C$ and the concentratio of acetaldehyde in air at the range of 0.07~0.94 mole% The pretreated metal-PC has been characterized by UV-VIS and XRD analysis. According to this study catalytic activity of metal -PC was improved by air pretreatment at 45$0^{circ}C$ for 1hr. Under this pretreatment condition Co-PC and Cu($alpha$)-PC were destroyed and new metal oxides were formed such as Co3O4 and CuO respectively. However Zn-PC retained its basic structure even afte air pretreatment. The order of catalytic activity on acetaldehyde combustion was summarized as follows : Zn-PC<Co-PC<CU($alpha$)-PC. It was found that the complete combustin of acetaldehyde with Cu($alpha$)-PC was accomplished at its concentrations below 0.2mole% (32$0^{circ}C$) and 0.6 mole%(35$0^{circ}C$) in air.