This study investigated the mutual perceptions among consumers, advertisers, and agencies on advertising regulation with sex appeal employing co-orientation model. The total numbers of 450, including 150 consumers, 150 clients, and 150 ad partitioners in agencies, were responded to the survey. Results indicated that there are differences among three groups in terms of perception on advertising regulation with sex appeal. In details, agencies only assume that they have the same perception on regulation about sex appeal in ads with clients’ perceptions. However, both of clients and consumers presumed that they have different perception on regulation about sex appeal in ads from other groups. Clients accurately assumed consumers’ and agencies’ perception on ad regulation with sex appeal. Agencies also accurately presumed clients’ perception on ad regulation with sex appeal but consumers’ perception. Consumers accurately assumed clients’ perception on ad regulation with sex appeal but agencies’ perception.