This feasibility randomized controlled trial will assess the acceptability, feasibility, and preliminary effects of an integrated mindfulness and exercise eHealth intervention, eMindExCare, among prostate cancer patients undergoing active treatment in Hong Kong. Participants will be randomized in a 1:1 ratio to either an 8-week eMindExCare intervention or an enhanced health education attention-control programme. eMindExCare integrates culturally adapted Cantonese mindfulness practices with home-based aerobic and resistance exercise delivered through Zoom, supported by home practice, exercise logs, and weekly reminders. The enhanced health education control programme will match the intervention group in contact time and engagement but will not include progressive aerobic training, resistance-band prescription, stationary bike provision, or a structured mindfulness curriculum. Feasibility and acceptability outcomes will include eligibility, consent, randomization, attendance, retention, questionnaire completion, missing data, and adverse events. Preliminary outcomes will include sleep quality, fatigue, pain, physical activity, mindfulness, motivation for exercise, and quality of life assessed at baseline, immediately post-intervention at week 8, and 3 months post-intervention.