Objective: Prior work has shown that negative aspects (e.g., conflict) of marriage or marriage-like relationships are associated with poor health of offspring, but much less is known about the effects of positive aspects (e.g., affection) of parental romantic relationships. This study investigated links between conflict and affection within parents’ romantic relationships and the health of youth with asthma. Method: Eighty youths with asthma aged 10–17 answered daily questions over a 4-day period about conflict and affection within their parents’ romantic relationship, as well as their own daily mood, asthma symptoms, and expiratory peak flow. Results: Multiple regression analyses revealed that romantic affection—but not conflict—was directly associated with higher expiratory peak flow. Further, there was a significant indirect effect of romantic affection via youth positive affect on lower asthma symptoms. Conclusion: These results are the first to our knowledge to demonstrate that youth-reported positive characteristics of parents’ romantic relationships are associated with better health among youth with asthma.