Background: Rosai–Dorfman disease (RDD) is a rare, benign disorder of non-Langerhans cell histiocytic origin with an unknown etiology, which can affect the skin and other organ systems. The incidence in the United States is approximately 1:200,000. In Mongolia, four cases have been registered over the past five years under the ICD-10 code D76.0. Case presentation: A 59-year-old female patient initially presented to the Dermatology Department of the National Center for Dermatology with clustered, elevated lesions on the medial aspect of the right thigh, including papules, plaques, and nodules of round to oval shape. Additionally, multiple erythematous macules and papules were observed on both lower legs. For diagnostic purposes, a histopathological examination was performed, revealing histiocytes with abundant cytoplasm and lymphocytes within the cytoplasm (emperipolesis). The diagnosis was confirmed based on dermoscopic and immunohistochemical findings. Management: The patient was referred to the Mongolian-Japanese Hospital of MNUMS, where the remaining nodular lesions were surgically excised in the surgical department. Further follow-up was referred to a hematologist. Computed tomography (CT) imaging was recommended. Cutaneous-limited RDD may resolve spontaneously in some cases; however, when multiple organ systems are involved or when associated forms are present, referral to hematology and oncology specialists for systemic therapy is required. Conclusion It is important to differentiate this disease from other dermatological conditions presented with macules, papules, and nodules through clinical evaluation, histopathology, immunohistochemistry, and dermoscopic examination.