Abstract: Beck’s series function algorithm is applied to obtain the boundary heat response characteristics of combined bodies. Each step of the algorithm is optimized. A mathematical model containing multi-temperature measuring points and multi-future time steps is established. A triangular waveform heat flux is assumed as the boundary condition to solve the direct heat conduction problem to obtain the temperature field in the object. Then temperatures at some points are chosen as the input condition to calculate the boundary heat response. The errors of the results of iteration for the heat fluxes are lower than 0.5% and the errors of temperatures are lower than 0.01%. The effects of the number of measuring points, the positions of the measuring points and future time steps on the calculating errors are analyzed. The calculating method can be used to study the boundary heat response characteristics of the package structure in the fire simulation.