Communal strength is the motivation to meet a partner’s needs without expecting anything in return. In the current study, we examined if the association between communal strength, life satisfaction or positive and negative affect depends on the attachment styles of people in romantic relationships. 78 dating couples completed questionnaires about their own communal strength, life satisfaction, positive and negative affect, and attachment styles. Our analysis results indicated that the effects of communal strength on life satisfaction and positive affect do not differ based on people’s attachment styles. The effects of communal strength on negative affect did not differ based on people’s attachment avoidance; however, the effects of communal strength on negative affect depended on people’s attachment anxiety. Specifically, for people with low attachment anxiety, higher communal strength predicted lower negative affect. Thus, for individuals who feel secure in their relationship, motivation to respond to partner’s needs results in less negative feelings. In contrast, for people with high attachment anxiety, higher communal strength was not associated with negative affect. Hence, people with high attachment anxiety may not experience all of the benefits of higher communal strength. Attachment style research is important for studying positive and negative affect of individuals in relationships, exploring how interactions occur between people in a relationship and will aid in the advancement of long-standing questions of how attachment behavior affects adults later in life.