A sensor assembly includes: a base with an installation space; an electrical connection member disposed on the base; a sensing unit including at least two physical sensors and one integrated circuit board; and a contact member disposed at one end of the base. The sensor assembly is a combination of the temperature sensor and the vibration sensor, the main physical parameters (including back clearance, collision, thermal displacement and lubrication) regarding the operation of the linear motion transmission device can be calculated based on the temperature signal and vibration signals, without requiring the installation of separate different sensors. Therefore, installation space is reduced. The sensor assembly is directly abutted against the linear motion transmission device to detect the change of various physical values in a most direct manner.