Abstract In the estimation of most reservoir parameters in well test, the reservoir is assumed to be isothermal which is practically not true due to the fact that there are heat sources from friction in the wellbore, work done by the drill bit and as well as thermal recovery. Although, this temperature change is small, it can serve other beneficial purposes in the reservoir and the wellbore. The research work used the small change in temperature to estimate reservoir parameters like permeability and skin factor. This research work brought out equations to be used in the estimation these reservoir parameters and the applied to field data. This research work is applicable in reservoirs where steam flooding and in situ combustion processes are used as the enhanced oil recovery methods. These result obtained for permeability was practically the same as the true reservoir permeability from field data although the same could not be said about the skin factor since that of the estimated and true value were quite different. This makes thermal transient testing a good substitute for the estimation of reservoir permeability. The same could not be said about the skin factor since it affect the pressure drop not temperature change. This research work brought out the idea that thermal transient testing can be used as a tool for estimating some reservoir parameters as well as verification for estimated reservoir parameters using other well test methods.