The measures against the coronavirus disease (COVID-19) pandemic, such as lockdown, pose a major challenge to those who manage work and caregiving demands. Drawing on social cognitive theory, which emphasizes the critical role of self-referent thought and human agency in overcoming obstacles and striving toward goals, the present longitudinal study (prepandemic, during lockdown, and postlockdown) investigated work-family balance self-efficacy (WFBSE) and work-family balance (WFB) among working informal caregivers of older adults (i.e., those who manage paid work and informal eldercare) during the COVID-19 pandemic (N = 132). As hypothesized, prepandemic WFBSE was positively associated with the level of WFB during lockdown. Prepandemic WFBSE also mitigated the relationship between perceived work demands and WFB as well as the relationship between perceived difficulty to use technology for caregiving and WFB during lockdown. Prepandemic WFBSE, however, did not buffer the relationship between perceived caregiving demands and WFB and the relationship between perceived difficulty to use technology for work and WFB. We also observed that WFB during lockdown was associated with increased postlockdown WFBSE. Collectively, our research reiterates the relevance and utility of self-efficacy in the crisis context and provides empirical evidence for the proposition that positive changes may occur in the face of adversity. (PsycInfo Database Record (c) 2022 APA, all rights reserved).