The invention discloses an attached resistance strain sensor assembly includes a sensor body, wherein substrates are respectively mounted at two ends of a lower end face of the sensor body, a heat insulation layer is provided between two of the substrates, the heat insulation layer covers the lower end face of the sensor body, an outer cover is covered above the sensor body, two ends of the outer cover are respectively mounted on the two substrates, and a wiring terminal is provided at one side of the outer cover. The sensor assembly can be mounted to a structural member by electric welding, so that the influence of high temperature on the performance of an elastic part in the sensor body during welding is reduced, the output value of the sensor is still in an expected range, and a more accurate load measurement value can be obtained.