Acurate estimate of porosity and permeability is important for characterization of porous media and especially for estimating storage and flowability. This work presents a model for estimating the permeability of a homogeneous reservoir based on transient pressure and temperature data during the process of opening and closing a well production valve. The estimation was obtained through the solution of an inverse problem in order to determine the permeability value that best adjusts the result of the computational model to the pressure and temperature data. The model consists of the single-phase solution of transient flow in a homogeneous reservoir radial described by the equations of conservation of energy, mass and Darcy s equation. The study was divided into two stages. Initially, synthetic data are generated through random perturbation to the results obtained from a direct simulation. After generation of the synthetic data, permeability estimation is obtained using an inverse problem. The developed method was tested for some cases by analyzing the accuracy of the estimated permeability value based on pressure, temperature and the combination of the two.