"Social media is increasingly finding a place for itself in all aspects of our lives. Social media is being increasingly used as a platform to conduct marketing and advertising activities (Alalwan, 2018). However, there is always a challenge in how organizations can figure out the results of social media marketing (Costa, Borges-Tiago & Tiago, 2018). Therefore, this study aimed at determining the effect of social media marketing on consumer brand relationships; brand engagement, brand loyalty, brand awareness among smartphone users in Egypt, moreover, to identify the effect of demographics and psychographics in this relationship. Smartphones have become an inseparable part of our daily lives. Nowadays, smartphones and social media go hand in hand as 92.5% of global browsing social media is through smartphones (Annual Digital Report, 2018). In recent years, mobile devices have taken social media marketing to a whole new level as users continually choose to access their networks remotely, via smartphones, tablets, and laptops. Thus, smartphone users have been chosen as population. Ex-post facto design has been chosen to achieve the research objectives. A cluster sample has been chosen and seven governorates out of 27 have been drawn randomly to collect data from. A questionnaire has been designed to measure the research variables. The instrument has been tested for reliability (Cronbach alpha) and validity (confirmatory factor analysis). A sample of 600 smartphone users (based on 4% confidence level) has been determined and 502 valid instruments have been returned. Independent sample t-test, regression, multi group analysis, and path analysis have been all used to test the research hypotheses. Results showed that social media marketing significantly affects brand engagement, brand loyalty, and brand awareness among smartphone users in Egypt. Moreover, consumers’ age, income, and education significantly affect these relationships. Finally, consumers psychographics significantly affected these relationships. Results were discussed. Based on results, several practical implications have been extracted. Therefore, several recommendations have been introduced. Based on the research limitations, several future research suggestions were presented. "