Background: This study assessed the potential effectiveness, acceptability and feasibility of a tailored mindfulness-based intervention (MBI, REMIND 2.0) for personal recovery among people with mental illness during the COVID-19 pandemic. Methods: In this pilot mixed methods randomized controlled trial, participants were assigned to either the MBI (n = 14) or the relaxation training (RT) (n = 14). Quantitative measures were used to assess primary outcomes, including personal recovery, mindfulness, self-compassion, resilience, and secondary outcomes, including depression, stress, anxiety, positive and negative moods, quality of life and general health at baseline (T0), post-intervention (T1) and one-month follow-up (T2). Quantitative interviews were conducted to explore the experiences and perceptions toward the MBI. Results: Results indicated significant group and time interactions for all outcomes except anxiety and stress. MBI participants showed significant improvements in all outcomes at T1, which were maintained at T2, except for positive mood. RT participants showed a significant decline in resilience but significant improvements in all secondary outcomes at T1, but all outcomes significantly declined at T2, except for anxiety and stress. MBI participants were receptive toward the programme in all aspects of personal recovery. Conclusions: The tailored MBI is a potentially effective, feasible and acceptable approach to facilitate personal recovery among people with mental illness. Differences between MBI and RT are discussed.