Abstract Case Description-In this clinical report, occurrence of a rare case of canine cutaneous inverted papilloma was discussed. A 4-year-old, intact, male German shepherd dog was presented with multiple skin lesions, located on the inguinal region near the root of penis, which have been progressively growing since two months ago. In close examination of the lesions multiple, firm, painful, and cup-shaped nodules in different sizes with a central pore filled with keratin were observed. Treatment and Outcome-Surgical excision and histological evaluation was done. Histologically this tumor was characterized by endophytic projections of the epidermis extending into dermis.Cytopathic effects included ballooning degeneration of keratinocytes, koilocytosis, irregularity of keratohyalin granules, and margination of nuclear chromatin. Numerous eosinophilic intranuclear inclusions were present within keratinocytes of endophytic lesion. Immunohistochemically, the tumor cells were intensely positive for pancytokeratin. On the basis of histopathological and clinical findings, the tumor was diagnosed as multiple cutaneous inverted papilloma. There was no recurrence or any other complications in post operative monitoring. Clinical Relevance-Inverted papillomas are relatively uncommon in dogs; whereas, the incidence of this tumor in the inguinal region is uncommon. Treatment of inverted papilloma was completed by surgical excision in ablating the tumor masses and preventing re-growth. 92 Case Description A 4-year-old, intact, male German shepherd dog was presented for treatment of multiple skin lesions, located on the inguinal region near the root of penis. The owner declared that the masses have been growing up rapidly through two months prior to presentation. On clinical examination; all vital signs (heart Rate, respiratory rate and rectal temperature) were in the normal range. On dermatological examination, multiple, firm, painful, and cup-shaped nodules in different sizes with a central pore filled with keratin were observed and the masses had well-demarcated border Treatment and Outcome Based on the clinical examination, cutaneous neoplasia was suspected and complete surgical excision of the masses was recommended. The dog was premedicated with 0/05 mg/kg acepromazine (KELA Laboratoria) intramusculary and anesthesia intravenously was induced with 10 mg/kg thiopental sodium (Sandoz) and was maintained with halothane 2% (Halothane BP, Nicholas Piramal). An elliptical incision was made in the skin around the lesion and the masses were dissected from subcutaneous tissues. The skin was sutured with Nylon (Monofil Polyamid, Supa) USP: 2/0 in interrupted suture pattern. Postoperative care included Cefazoline (Exir Pharmaceutrical Co.) at 20 mg/kg intramuscularly, every 12 hours for 3 days. The removed masses were fixed in 10% neutral buffered formalin, processed routinely, embedded in paraffin, sectioned at 5 µm thickness, stained with hematoxylin and eosin, and studied with a routine light microscope. Immunohistochemistry of additional section was performed with Avidin-Biotin complex method by using monoclonal antibodies for pancytokeratin antibody (1/500). Microscopic examination at the nodules revealed cupshaped epidermal proliferation with centripetal papillary projections into dermi