Attempts to improve others' feelings have positive consequences, while attempts to worsen others' feelings have negative consequences. But do such effects depend on the motives underlying these attempts? In an experimental study, we tested whether leaders' apparent motives influence the effects of their interpersonal emotion regulation on followers. We found that the positive effects of using affect-improving (vs. affect-worsening) strategies on relational outcomes and discretional performance outcomes were largely enhanced when the leader exhibited prosocial motives but diminished when the leader exhibited egoistic motives. Our findings add nuance to our understanding of the effects of interpersonal emotion regulation at work. Practitioner points: When leaders try to influence their followers' emotions, the consequences not only depend on the type of strategy used (improving vs. worsening), but also the leaders' apparent motives. If egoistic (vs. prosocial) motives underpin leaders' interpersonal emotional regulation, the positive effects of affect-improving (vs. affect-worsening) on leader–follower relationship quality and follower discretional performance are significantly reduced. Leaders should be aware of the behaviours they use during interactions with their followers as well as how their motives might be perceived.