  In this paper, we investigate the null geodesics of the static charged black
hole in heterotic string theory. A detailed analysis of the geodesics are done
in the Einstein frame as well as in the string frame. In the Einstein frame,
the geodesics are solved exactly in terms of the Jacobi-elliptic integrals for
all possible energy levels and angular momentum of the photons. In the string
frame, the geodesics are presented for the circular orbits. As a physical
application of the null geodesics, we have obtained the angle of deflection for
the photons and the quasinormal modes of a massless scalar field in the eikonal
limit.
