On the stability of Timoshenko cantilever beam subjected to a follower force, the influence of the characteristics of elastic constraints at the free end is studied. The equations of rnotion and boundary conditions of this nonconservative elastic system are estabilished by using the Hamilton`s principle. Upon evaluation of the stability of this system, the effect of shear deformation and rotatory inertia is considered in calculation. Using cowper`s formulae Timoslienko`s shear coefficient K are determined. From this investigation it is found that the constrain parameter have an appreciable stabilizing effect in this nonconservative system. Moreover, it is obvious that the small values of K decrease the flutter load of this system.