Merkel cell carcinoma (MCC) is an uncommon, neuroendocrine skin tumor with an aggressive clinical course. The etiology of the disease is unknown, although sun exposure and immunosuppression may play a role in its development. Coexistence of MCC with chronic lymphocytic leukemia (CLL) is extremely rare and to our knowledge it has been previously described in only 8 patients. We report a 51-year-old woman who presented with a red lump on the right cheek diagnosed as MCC. She had been diagnosed as having CLL 3 years earlier and was treated with 4 courses of cladribine (2-CdA) and subsequently with 4 courses of 2-CdA combined with rituximab. MCC was diagnosed on the basis of histological and immunohistochemical evaluation 2 months after the last course of 2-CdA and rituximab. Surgical excision with tumor-free margins was performed and local adjuvant radiotherapy was applied. Histopathological and immunohistochemical evaluation of the cervical lymph node specimens showed monotonous and diffuse infiltrate of small CD5+, CD20+, CD23+ lymphocytes and no MCC cells were present. To our knowledge, this is the first reported case of MCC occurring in CLL patients soon after treatment with 2-CdA and/or rituximab. The development of MCC in our patient may suggest that this complication rarely observed in CLL patients may have a link with strongly immunosuppressive therapy with 2-CdA and rituximab.