The unprecedented popularity of social media outlets have forced scholars to inquire about their marketing effectiveness, especially in the hotel industry. This study attempted to explore the marketing effectiveness of two different social media sites (Facebook and Twitter) in the hotel industry. Integrating the attitude-toward-the-ad (Aad) model with the concepts of attitude-toward-social-media-page, the study proposed a theoretical model of hotel social media marketing effectiveness. Based on the data collected from an online survey, the goodness of fit of the model implied that the Aad model provides an appropriate theoretical framework to explain the marketing effectiveness of social media in the hotel industry. The results revealed that hotel customers’ social media experiences influence their attitudes-toward-social-media-site, which in turn influences their attitudes-toward-hotel-brand, and that hotel customers’ attitudes-toward-hotel-brand affects their hotel booking intentions and, in turn, intentions to spread electronic word of mouth. The study also indicated that different social media sites demonstrate the same marketing effectiveness, suggesting that hotel managers use the same marketing tactics for Facebook and Twitter marketing.