Population aging has increased reliance on family carers, whose psychosocial burdens and support needs vary by life stage. This exploratory study aimed to compare psychosocial care burdens and support needs between middle-aged family carers (MFCs) and older family carers (OFCs) providing home-based care in Japan from a life-stage perspective. A cross-sectional survey was conducted among family carers registered with a community general support center in Sapporo, Japan. Data from 153 respondents were analyzed. Psychosocial care burden was assessed across perceived burden, underlying causes, and broader life challenges. Support needs were evaluated based on preferences for 20 types of services and supports. Overall, 60% of MFCs and 53.9% of OFCs experienced care burden. MFCs reported significantly greater burdens related to family relationships (Cramer’s V = 0.168) and work-related concerns (Cramer’s V = 0.235). They also expressed higher needs for Care Leave Accessibility, Flexible Work for Care, and Carer Job Support, with small-to-moderate effect sizes. The findings suggest that psychosocial burdens and support needs among family carers may vary across different age-defined life stages. Middle-aged carers balancing work and family responsibilities face distinct challenges, underscoring the need for targeted policies, workplace support, and life-stage-responsive, role-sensitive support systems in aging societies.