Objectives: This study examined the dyadic effects of self-rated health on the life satisfaction of family caregivers. The effects of the use of long-term care services were also explored to investigate whether support through care services is associated with the life satisfaction of family caregivers. Methods: The data were drawn from the sixth wave (2016) of the Korean Longitudinal Study of Aging. Caregivers who used long-term care services for older family members, and spouses of the caregivers, were identified. A total of 81 married caregiver couples were analyzed using the actor-partner interdependence model. Results: The study showed that better self-rated health of caregivers was associated with higher levels of life satisfaction (B = 8.87, p < 0.001). Better self-rated health of the caregivers was also associated with higher life satisfaction of their spouses (B = 6.01, p < 0.05). In addition, the results suggested that the use of long-term care services for patients was associated with the life satisfaction of both caregivers (B = 14.57, p < 0.01) and their spouses (B = 12.51, p < 0.05). Discussion: Our findings suggested mutual influences among family caregivers on their life satisfaction. In addition, long-term care services for patients may improve the life satisfaction of other family members. More support through long-term care services for people with care needs is required to increase the life satisfaction of family caregivers. The diverse relationships among family caregivers should be taken into consideration when developing policies and interventions.