Low temperature cracking on asphalt material is one of the serious distresses for asphalt pavement built in northern U.S., Europe and Canada. Thermal stress is a key factor for measuring (and estimating) the resistant capability of asphalt pavement against low temperature cracking. For this reason, many road agencies have recognized thermal stress as a crucial parameter for evaluating the low temperature performance of asphalt pavement materials. Thermal stress is conventionally computed through two steps. First, the relaxation modulus E(t) is generated thorough the conversion of the experimental creep compliance data D(t). Then thermal stress (T℃) is numerically estimated solving convolution integral. In this paper, a one-step approach to the calculation of thermal stress is proposed. This method is based on Laplace transformation. Thermal stress and corresponding critical cracking temperature obtained with single- and double-step procedure on a set of three mixtures are graphically and statistically compared. It is observed that the application of Laplace transformation provides reliable computation results of thermal stress compared to the conventional computation approach.