Caregivers of men with prostate cancer report high burden, and there is a need to develop cost-effective programs to support them in their roles. This study reports on the acceptability of a dyadic, Tailored, wEb-based, psychosocial and physical activity (PA) self-Management PrOgram called TEMPO. TEMPO was accessed by a convenience sample of 19 men with prostate cancer and their caregivers (n = 18), as well as six health care professionals (HCPs). User feedback was gathered via semi-structured qualitative interviews. Data were analyzed using thematic analysis. Most dyads were satisfied with TEMPO, particularly with the dyadic feature of TEMPO, the focus on goal setting to integrate self-management, and the extensive health library. The patients and caregivers motivated each other as they worked through TEMPO. Most goals to achieve during TEMPO pertained to increasing PA, followed by learning physical symptom management. One unanticipated benefit of TEMPO for the dyads was improved communication. HCPs agreed that TEMPO was a novel approach to online cancer self-management and they echoed the benefits reported by dyads. Key suggestions for improving TEMPO were to reduce repetition, tailor content, add more exercise ideas, and have more printing options. This study provides a strong foundation on which to plan a larger trial.