For patients with chronic diseases, especially those with chronic low back pain, the patient-physician relationship is significant for treatment adherence. In a sample of N = 688 low back pain patients, we examined the hypothesis that aspects of the patient-physician relationship (e.g. satisfaction with care, trust in the physician, patient participation) have a significant association with outcomes (pain, disability, quality of life, pain-related psychological impairment) after a multimodal treatment program (rehabilitation) after adjusting for a number of sociodemographic, medical, and psychological factors. Results show that the patient-physician relationship is significantly associated with the outcome. In the medium term (6 months after rehabilitation), the effect of the patient-physician relationship is clearer than in the short term (end of rehabilitation). In addition, risk factors for less improvement are female gender, higher age, low income, comorbidity, low treatment motivation, fear avoidance beliefs, and external locus of control. Future studies should examine the causal paths between the relationship variables and the outcome variables.