  We study the gravitational lensing by a Kerr-Sen Black Hole arising in
heterotic string theory. A closed form expression for the bending angle of
light in equatorial plane of Kerr-Sen Black Hole is derived as a function of
impact parameter, spin and charge of the Black Hole. Results obtained are also
compared with the corresponding cases of Kerr Black Hole in general relativity.
It is observed that charge parameter behaves qualitatively similar as the spin
parameter for photons travelling in direct orbits while behaves differently for
photons in retrograde orbits around Black Hole. As the numerical value of the
Black Hole charge increases, bending angle becomes larger in strong field
limit. Further it is observed that this effect is more pronounced in case of
direct orbits in comparison to the retro orbits. For both the direct and retro
motion, the bending angle exceeds 2\pi, which in turn results in multiple loops
and formation of relativistic images.
