Recently, main marketing channels of brands are moving from traditional media to social media. Social media platforms are regarded as an effective tool for developing brand equity, and companies are expanding the use of social media content to induce customer engagement. However, there are not enough studies to verify the complete path of how a company's social media strategy affects brand equity through customer engagement, and it is limited in terms of differences in the effectiveness of social media content strategies according to culture. This study analyzed whether the characteristics of social media content mediate customer engagement and have a positive influence on brand equity. In addition, the moderating effect was analyzed to see if there were any differences in the effects of these pathways according to the cultural characteristics of the United States and Korea. Facebook data of US and Korean companies from 2013 to 2018 and brand equity data of Interbrand were collected, and a total of 405 company-year data were analyzed by the PLS-SEM method. As results, it was found that customer engagement mediates the relationship between social media content characteristics and brand equity. In addition, it was found that these paths differ according to culture.