Rosai Dorfman disease (RDD) is a rare subset of non-Langerhans cell histiocytosis mainly involving the lymph nodes. Cutaneous manifestation occurs in approximately 10% of the patients, which may be associated with systemic involvement. Primary cutaneous RDD is extremely rare and poses a diagnostic challenge. We present a case of a middle-aged male presenting to a tertiary care hospital in India with a painless, progressive abdominal lump for 2 years. Abdominal examination revealed a non-tender, firm, solitary lump in the right lumbar region extending to the umbilicus, with overlying skin changes and fixity to the underlying muscle. A contrast-enhanced computed tomography of the abdomen revealed a 2.9 × 7.3 × 4.6 cm homogenously enhancing soft tissue density mass in the subcutaneous plane in the right supraumbilical region with preserved fat planes with underlying rectus abdominis muscle and few sub-centimetric satellite nodules. Image-guided core-cut biopsy suggested Rosai Dorfman disease. The patient was kept on medical management with 30 mg of oral prednisolone for 3 months, with no reduction in the size of the lump. He subsequently underwent wide excision of the lump with an uneventful postoperative course. Final histopathology revealed histiocytes displaying emperipolesis. They were diffusely immunopositive for S100 protein and CD68, CD163, and negative for CDIa and langerin, confirming RDD. The patient is under a 3-monthly follow-up and has had no recurrence of the lump. Cutaneous RDD is an extremely rare disease with limited understanding of its etiology and optimal management, thus highlighting the need for further research.