Studies have consistently found that relationship conflict adversely affects work outcomes, prompting the conclusion that such conflict should be avoided. Challenging this established finding, we propose that relationship conflict has a positive effect on creativity when the relational self is salient. Specifically, we hypothesize that relational selves' relationship-focused goal may be frustrated within a conflictual (vs. harmonious) relationship situation, triggering cognitive persistence that boosts their creativity by causing them to think in more depth and detail about their conflict. Data from the US (Experiment 1) and Korea (Experiment 2) supported our hypotheses. A subsequent study extended these findings to process conflict (Experiment 3). Our research highlights the overall finding that frustration of goals that are meaningful for individuals promotes their creativity through the mediation of cognitive persistence.