About 70,000 people were affected with breast cancer in Japan in 2012, and the prevalence rate was 113 per 100,000 people. Although breast cancer affects a high number of patients and the incidence rate is high, the 5-year relative survival rate is 91.1%. Among cancers with high survival rates, thyroid cancer has the highest rate, skin cancer is second, and breast cancer is third [1]. Thus, treatment of breast cancer is highly likely to be lifesaving.Breast cancer treatment is performed through a combination of surgical therapy, radiotherapy, chemotherapy, and endocrine therapy. Over time, surgical therapy has changed to less invasive surgery. Sentinel lymph node biopsy reduces upper limb dysfunction associated with breast cancer surgery. The onset of upper limb dysfunction was reported to occur in 66% of patients in an axillary lymph node dissection group and in 36% in a sentinel lymph node biopsy group [2]. However, after sentinel lymph node biopsy, the frequency of limited shoulder joint flexion is 37−100%, that of limited abduction is 40.8−100%, and that of upper limb Abstract: Purpose: The purpose of this study was to investigate the psychological effects on health-related quality of life (HRQOL) of postoperative range of motion of the shoulder joint and subjective symptoms in patients with breast cancer who underwent rehabilitation. Methods: In 79 patients with breast cancer surgery who underwent rehabilitation during hospitalization, we investigated temporal changes in the range of shoulder joint function (flexion of shoulder joint/abduction angle), postoperative subjective symptoms (surgical site pain, tightness, and anxiety regarding the disorder), and HRQOL scales (FACT-B and EQ-5D-5L) from before to 6 months after surgery and examined the factors relating to HRQOL. Results: The range of shoulder joint movement was significantly decreased even from pre-operation to 1 month after surgery, but subjective symptoms had significantly improved at 6 months after surgery. Multivariable regression analysis showed that postoperative feelings of anxiety felt at 1, 3, and 6 months after surgery were a significant variable influencing the FACT-B and EQ-5D-5L scales. The path coefficients of the standard partial regression coefficients of breast cancer patients at 6 months postoperatively by covariance structure analysis were 0.66 for the EQ-5D-5L effective value, 0.94 for FACT-B, 0.47 for shoulder joint function, and −0.64 for postoperative subjective symptoms as the latent variables of HRQOL. Conclusion: The results suggested the importance of interventions that focus on postoperative subjective symptoms to possibly improve not only patient function but also postoperative HRQOL.