Hot electron magnetotransport in a spin-valve transistor has been theoretically explored at finite temperatures. We have calculated the parallel and anti-parallel collector current by changing the relative spin orientation of the ferromagnetic layers at finite temperatures. In this model, hot electron energy redistribution due to spatial inhomogeneity of Schottky barrier heights and hot electron spin polarization in the ferromagnetic layer at finite temperatures have been considered. The results of these model calculations agree with experimental data in a semi-quantitative manner. We therefore suggest that both these effects should be taken into account when one explores the hot electron magnetotransport in a spin-valve transistor at finite temperatures.