The detection statistics of a light beam with randomly fluctuating intensity are of considerable interest. This paper derives an explicit form for the photocount statistics of a laser beam in the presence of an interfering background radiation. The result can be readily utilized to obtain the over‐all photocount statistics by appropriate averaging over the random laser‐beam intensity. The technique is quite suited to experimentally determined probability density. The analysis developed in this paper is applied to the propagation of light through turbulent media. Numerical results are obtained for the over‐all photocount statistics for the two often considered probability distributions in this case: lognormal and Rice‐Nakagami. The photocount distribution for the lognormally fluctuating medium is then utilized to obtain the probability of error and information rate for a laser binary communication system.