Among structural health monitoring (SHM) techniques, Lamb waves is frequently used as diagnostic tools to detect damage in plate-like structures. Temperature variation can cause significant changes in guided-wave propagation and transduction for SHM. In this paper, a transient dynamic finite element simulation of Lamb wave for damage detection in a stiffened plate under different temperature condition is carried out on the commercial finite element code ANSYS platform. Simulations are conducted over a temperature range of 25-75°C using 275 kHz as excitation frequencies. The changes in temperature-dependent material properties are used to measure the differences in the response signal’s waveform. Then controlled experiments examine changes in Lamb wave propagation and transduction using PZT-5A piezoelectric wafers under quasi-statically varying temperature (from 5°C to 60°C). The baseline selection method and baseline signal stretch method are used to compensate the temperature influence on Lamb wave propagation. The results of the numerical simulation and experiments demonstrate the effectiveness of the temperature compensation approach and the simulated damage on the aluminum plate can be detected effectively under elevated temperatures environment.