This study examined the effectiveness of advertising in the context of commercialization congruence between online advertising and Web sites. Specifically, we separated commercialization congruence into commercial and noncommercial sectors, and drew from schema-congruence theory to consider the effects of commercialization congruence that may influence attitudes toward advertising. We employed the laboratory experiment method to manipulate the commercialization level of the Web site and the banner advertisement to verify attitudes toward advertising, before testing them according to commercialization congruence between advertising and the Web site. The findings revealed that our subjects’ attitudes toward commercial advertising were significantly higher (lower) than for noncommercial advertising on commercial Web sites (noncommercial Web sites). This study contributes to online advertising research, can assist advertisers in their understanding of the importance of commercialization congruence, and serves as a reference for advertisers considering the placement of advertisements on Web sites.