Nowadays, in order to attract talented employees, the factor of employer branding has become critical. Internal employer branding features include the working environment, work-life balance, compensation and benefits, training and development, and corporate social responsibility (CSR). Besides, employer branding fosters a professional working environment, enhancing the reputation of the business. In addition, organizational citizenship behavior (OCB) is a voluntary behavior of employees, not recognized by regular reward systems. The purpose of this study is evaluating employer branding’s influence on employee retention and OCB through employee satisfaction. We use questionnaires to collect data from participants (N = 125) in many industries in Vietnam. Hierarchical regression analysis is used to examine the hypotheses. And the findings suggest that there is a significant effect of employer branding on employee retention and OCB via employee satisfaction as a mediator. The findings show a positive relationship between outcomes of employer branding (work environment, work–life balance, training and development, compensation and benefits, and CSR) and employee retention. In addition, a positive relationship is found between employers and OCB as well. This study expands several solutions for businesses to enhance employer branding and positively impact employer branding to retain employees and OCB.