Cancer-related pain is prevalent and has debilitating effects on patients and their family. The effects of cancer pain can be curtailed if the family members caring for the patient receive essential support to enhance their capabilities for cancer pain management. Little has been done to study the available support to family caregivers (FCGs) towards pain management in adult cancer patients (ACPs) living in resource-limited countries where the burden of cancer is on the rise. This study evaluated the influence of an education intervention delivered in the home setting on FCGs' knowledge and self-efficacy (SE) for pain management in ACPs. One-group pre-/post-test design was used in a sample of 54 FCGs who had been caring for ACPs suffering from pain for at least 1 month. Data were collected using the Family Pain Questionnaire and Caregiver Pain Management SE Scale. The FCGs' mean knowledge score post-intervention (26.69 ± 10) was higher than the baseline (45 ± 12.9), and the difference was statistically significant (t = 10.382, p = 0.000, CI = 17.12-25.43). Additionally, the FCGs' mean SE score post-intervention (1003.30 ± 191) was higher than the baseline (648.3 ± 273.4), and the difference was statistically significant (t = - 8.52, p = 0.000, CI = - 438.6-- 271.4). The home-based education intervention significantly and positively influenced the FCGs' knowledge and SE for pain management while at home. Cancer pain management educational interventions delivered at home should be considered as one of the strategies for enhancing cancer care in resource limited settings.