In this paper a new reconstruction algorithm of the Electrical Impedance Tomography (EIT) will be presented. The least-square method is applied and a new formulation similar to that of the perturbation method is found. Our main difference with the perturbation lies with the sensitivity matrix, which in our case is replaced by the Jacobian matrix, defined from the partial derivatives of every sensing electrode pair voltage difference with respect to every element's conductivity. The mutual position between the active electrodes is chosen to give optimum sensitivity. From the results it can be seen that the algorithm presented here has a better convergence and needs less iterations.