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Background: Cutaneous metastases of colorectal cancer (CRC) are rare, occurring in 0.7% to 5% of cancer patients.Furthermore, the molecular subtypes of cutaneous metastasis of CRC are unclear.Here, we present a rare case of cutaneous metastasis of high-frequency microsatellite instability (MSI-high)/BRAFV600E-mutant cecum cancer.Case presentation: A 77-year-old woman presented at the outpatient clinic with a subcutaneous mass on her left back.An excisional biopsy was performed and metastatic cutaneous adenocarcinoma was diagnosed.A computed tomography scan of the thorax and abdomen showed thickening of the cecum wall, the presence of pericolic lymph nodes, multiple masses in the liver, and a single nodule in the right lung.Right colectomy with D2 lymphadenectomy and functional end-to-end anastomosis was performed because of the almost-complete intestinal obstruction.The expression of KRAS wild type, BRAFV600E mutation, and MSI-high was detected in the cecum cancer using molecular pathological examination.She received chemotherapy with XELOX + BEV regimen (capecitabine + oxaliplatin + bevacizumab).After four administrations, a computed tomography scan showed reduction of distant metastases, which suggested partial response. Conclusions:We encountered a rare case of cutaneous metastasis of MSI-high and BRAFV600E-mutant cecum cancer.In the future, it will be necessary to accumulate more cases to identify clinical features and more effective treatments for CRCs with cutaneous metastasis.