This study aims to analyze the influence of work stress, procedural justice, and organizational climate on organizational citizenship behavior with employee engagement as a mediation variable in PD BPR Bank Sleman. Overall population in PD BPR Bank Sleman as many as 130 people, sampling method in this study using total sampling. Data collection technique used is survey method by using questionnaire. Data analysis technique used is Structural Equation Modeling. The results showed that work stress had a negative and significant effect on employee engagement and organizational citizenship behavior, organizational climate and employee engagement had a positive and significant effect on organizational citizenship behavior, procedural justice and organizational climate had a positive and significant effect on employee engagement, whereas procedural justice did not have significant influence on organizational citizenship behavior, which means rejecting the hypothesis in this study. Organizational climate and employee engagement are dominant or greatest variables in influencing organizational citizenship behavior so special attention and improvement needs to be made by the management of PD BPR Bank Sleman.