The present study had been designed to explore impact of social media marketing on customer's satisfaction and moderating role of the trust of customer's on FMCG products. Companies are currently utilizing social networks to advance data about their brands. Online social networking sites such as Facebook, Twitter and My Space etc. have a significant impact on customer's life. This social media has a direct effect on how the clients impart, offer data, keep up their profiles and secure connections with their friends. The rapid use of social media marketing, organizations have to change their way to respond consumer's needs and wants and changing the way they respond to their competitors. The growth of social media marketing and electronic word of mouth has allowed consumers to interact with each other in the virtual world and to share their perceptions and feelings towards FMCG items which are available on social media sites. Because of commitment of individual's social networking particularly Facebook have part more commitment in social activism in Pakistan. Numerous social changes has been perceived and reported by the traditional media. The major objective of study is to explore the impact of social media in terms of satisfying customer needs for purchase decisions of FMCG items. The present study was conducted in the Faisalabad and Lahore cities. 5 shopping malls were selected from each city as population and the sample of 204 respondents was selected conveniently from the customers of these shopping malls. Moreover, data was collected by using mall-intercept technique with the help of questionnaire and analyzed by using SPSS. Frequency, percentage and simple linear regression were used to check the central tendency. When regression was applied the value of R2 was 0.201 which depicts that 20.10 % customer satisfaction was due to social media. Interaction term was created to check the role of customer trust as moderation effect. Change in R2 was 0.239 which depicts that the relationship of social media and customer satisfaction was increased up to 23.90 % in the presence of customer trust. Customer trust played significant role as moderator in the relationship of social media and customer satisfaction. It was found on the basis of statistical techniques majority of the respondents were satisfied with the social media marketing. This study will help to the companies to target their customers via social media according to their needs and wants. This study will also help those companies who did not yet start to use social media for marketing purpose.