We report the unique occurrence and treatment of spontaneous multiple insufficiency fractures after sepsis in a patient with rheumatoid arthritis (RA). The patient was a 53-year-old woman with a 13-year history of RA. Her disease activity was not influenced by a disease-modifying antirheumatic drug (DMARD) regimen that included bucillamine, D-penicillamine, gold, sulfasalazine, and methotrexate. Due to an increased disease activity, her DMARD treatment regimen was changed to leflunomide. She had also undergone corticosteroid therapy with prednisolone ranging from 10 to 15 mg daily over the previous 8 years. She first presented with a wound infection at the surgical site of resection arthroplasty on her left foot, which had caused hematogenous dissemination that led to pelvic abscess and sepsis. For the next 2 years, she experienced multiple insufficiency fractures in parts of the ilium, sacral body, sacral ala, three thoraco-lumbar vertebral bodies (T12, L1, and L2), and subcapital femoral neck without low energy trauma. Postmenopausal osteoporosis, pelvic abscess, sepsis, decreasing daily activity, high RA disease activity, and high-load corticosteroid therapy were considered to be the causes of these fractures. Nonspecific symptoms such as low back pain and fever delayed diagnosis, which may have led to secondary fractures. Although her course after treatment was satisfactory during the study period, we recommend taking repetitive radiographs to detect insufficiency fracture for RA patients with continuing pain and reducing the corticosteroid dose to prevent infection and fracture.