While being a workaholic supervisor may be viewed as admirable due to their commitment to work, existing findings on its effects on subordinates are mixed. Drawing upon the principle learning perspective and activation theory, we propose a curvilinear relationship between supervisor workaholism and subordinate job performance and investigate the moderating role of subordinate social-related social media usage. Specifically, we suggest that subordinate job performance increases (decreases) as supervisor workaholism increases from low (moderate) to moderate (high) levels and that this inverted U-shaped relationship becomes flatter when subordinates have higher social-related social media usage. The results, based on a multi-source survey collected from 321 supervisor-subordinate dyads, support the predictions. Our research moves beyond linear thinking and suggests that there exists an optimal level of supervisor workaholism that maximizes subordinate job performance. We also provide insights into the ongoing debate and potential ethical concerns surrounding whether employees should use social media at work. Implications for practice and future research are discussed.