PURPOSE: Loving-kindness meditation has been used for centuries in the Buddhist tradition to develop love and transform anger into compassion. This pilot study tested an 8-week loving-kindness program for chronic low back pain patients. METHOD: Patients (N = 43) were randomly assigned to the intervention or standard care. Standardized measures assessed patients' pain, anger, and psychological distress. FINDINGS: Post and follow-up analyses showed significant improvements in pain and psychological distress in the loving-kindness group, but no changes in the usual care group. Multilevel analyses of daily data showed that more loving-kindness practice on a given day was related to lower pain that day and lower anger the next day. CONCLUSIONS: Preliminary results suggest that the loving-kindness program can be beneficial in reducing pain, anger, and psychological distress in patients with persistent low back pain. IMPLICATIONS: Clinicians may find loving-kindness meditation helpful in the treatment of patients with persistent pain.