CD30 immunohistochemistry (IHC) is a laboratory test used to detect the presence of the CD30 protein (Cluster of Differentiation 30) on cells in a tissue sample using special antibodies and staining techniques.

CD30 is a cell surface receptor belonging to the tumor necrosis factor (TNF) receptor family and is normally expressed on a limited subset of activated lymphocytes. It becomes strongly expressed in certain lymphoid malignancies, making it an important diagnostic marker.