A web thickness measuring equipment and a method of measuring a web thickness. A web thickness measuring equipment includes: a roller that is rotatable and configured to wind a web; a detection unit that detects a light amount on an outer circumferential surface of the roller or an external surface of the web wound on the roller, and detects a magnetic field of an internal surface of the web opposite to the external surface; and a processor unit configured to obtain a thickness of the web by generating profile data of the outer circumferential surface of the roller, generating displacement amount data of a target external surface of the web, generating displacement amount data of a target internal surface of the web, and comparing the displacement amount data of the target external surface of the web with the displacement amount data of the target internal surface of the web.