Using data from the China Health and Nutrition Survey (CHNS), this study investigated the impact of informal care on female caregivers' subjective well-being in China. We found that informal care significantly reduced the subjective well-being of female caregivers using the instrumental variable (IV) ordered probit model. Our results revealed that the care effect on subjective well-being was more significant for rural caregivers than for urban caregivers. The more hours or more recipients care was provided for, the greater the negative impact on subjective well-being.