A skin biopsy involves the removal and laboratory examination of a portion of skin that appears abnormal. It can help a physician to diagnose several different skin disorders, including skin cancer, fungal or bacterial infection, or other conditions such a psoriasis or lichen planus.

One of several different types of biopsies may be performed on a patient, depending on the nature of the skin abnormality. From least invasive to most invasive, these include shave biopsy, punch biopsy, incisional biopsy and excisional biopsy.