The present research tested the unique associations between attachment and basic psychological need fulfillment in relationships. Past research shows that anxious and avoidant attachment are associated with distinct patterns of relationship behaviors, wherein anxious attachment is related to excessive attention to the relationship and avoidant attachment is related to detachment from the relationship. Specifically, we explored the role of romantic partner’s attachment in predicting each other’s experiences of relatedness, autonomy, and competence. Across two samples of undergraduate romantic couples ( n_{sample 1} = 156, n_{sample 2} = 264), one’s own anxious and avoidant attachment predicted generally lower basic psychological need fulfillment. Having a more anxiously attached partner predicted higher relatedness but lower autonomy, whereas having a more avoidantly attached partner predicted lower relatedness but higher autonomy need fulfillment. These results extend prior research, suggesting that one’s partner’s anxious and avoidant attachment has distinct implications for one’s own outcomes.