Researchers have investigated display advertising in the past several years from different perspectives but only in connection to traditional Web sites and not specifically for social networking sites. Facebook is the most prominent social networking site in term of number of users and its main source of revence is its online advertising business. Having display advertising in their virtual space is the reason why social networks are able to offer free service and as such the need to understand how users perceive it arises The most important way of understanding users' perceptions about the advertising, it is necessary to examine the factors that affect the attitude-toward-the-ad. Ad perceptions, ad credibility, attitude toward advertisers, attitude toward advertising and mood have been identified by previous researcher as clearly influencing the attitude toward specific ads.