In earth-satellite-earth laser communication links,laser beam passes through the earth's atmosphere which occasionally contains clouds. The important distortion effects imposed by clouds in the atmosphere are temporal broadening of the signal and attenuation due to multiple scattering. Multiple scattering problem arises when light propagates through an optically thick clouds hence the photons encounter a number of scatterers before emerging from the medium. In the present work, Monte Carlo simulation is used to show the trajectory of photons (rays) in the medium and interaction between the particles and laser beam.Results show that the output beam is spread over time and space depending on the random nature of the medium.