  In the present paper we study the geodesic structure of the
Janis-Newman-Winicour(JNW) space-time which contains a strong curvature naked
singularity. This metric is an extension of the Schwarzschild geometry when a
massless scalar field is included. We find that the strength parameter $\mu$ of
the scalar field effects on the geodesic structure of the JNW space-time. By
solving the geodesic equation and analyzing the behavior of effective
potential, we investigate all geodesic types of the test particle and the
photon in the JNW space-time. At the same time we simulate all the geodesic
orbits corresponding to the energy levels of the effective potential in the JNW
space-time.
