BackgroundPolo‐like kinase‐1 (PLK‐1) is one of the key regulators of cell cycle progression. Increased expression of PLK‐1 was observed in several tumor types.MethodsWe immunohistochemically assessed PLK‐1 expression in neoplastic and stromal compartments of 96 cutaneous melanomas, and analyzed associations between PLK‐1 expression and clinicopathological characteristics.ResultsPLK‐1 expression in cancer cells was not associated with basic clinical (eg, age, gender and tumor location) or histopathological (eg, Breslow thickness, mitotic rate and ulceration) parameters. However, increased PLK‐1 was more frequent in tumors with concurrent regional nodal metastases and positive sentinel lymph node biopsy status. All primary tumors associated with co‐existing distant metastases exhibited high PLK‐1 expression in melanoma cells. Conversely, PLK‐1 expression in stromal cells was more frequent in tumors without nodal metastases. PLK‐1 expression in both compartments was not associated with survival.ConclusionPLK‐1 expression is associated with metastatic potential in cutaneous melanoma.