贝克痣（Becker's nevus），又称贝克黑素沉着病，贝克色素瘤，是一种男性皮肤紊乱病症。这种痣一般以不规则色素沉着，首先出现在躯干部或肩臂部，而后逐步扩大、增厚，通常伴随生长被毛，1948年由美国皮肤医生萨缪尔·威廉·贝克首先发现并记录。贝克痣的成因未明，有天生带有此痣的男童案例，一半案例发生在0-10岁之间，另一半发生在10-20岁之间，75%的患者为浅褐色，平均发病面积约125平方厘米。临床一般使用激光仪器进行治疗。

Becker's nevus (also known as "Becker's melanosis," "Becker's pigmentary hamartoma," "Nevoid melanosis," and "Pigmented hairy epidermal nevus") is a skin disorder predominantly affecting males. The nevus generally first appears as an irregular pigmentation (melanosis or hyperpigmentation) on the torso or upper arm (though other areas of the body can be affected), and gradually enlarges irregularly, becoming thickened and often hairy (hypertrichosis). The nevus is due to an overgrowth of the epidermis, pigment cells (melanocytes), and hair follicles. This form of nevus was first documented in 1948 by American dermatologist Samuel William Becker (1894–1964).