In this paper a new nonlinear guidance law with finite time convergence is proposed. The second order integrated guidance and control loop is formulated considering a first order control loop dynamics. By transforming the state equations to the normal form, a finite time stabilizer feedback linearization technique is proposed to guarantee the finite time convergence of the system states to zero or a small neighborhood of zero before the final time of the guidance process. However, some feedback quantities such as high order LOS rate derivatives are not directly measurable and therefore, a finite time observer is proposed to have a finite time output feedback guidance law for more practical applications. Simulation results show the effectiveness of the proposed guidance law.