In this paper we derive a new mixed Poisson distribution which includes the negative binomial, Poisson-Lindley, Poisson-Lomax, Poisson-Beta type II, and Poisson-F distributions. Recurrence relations for calculating the probabilities and factorial moments of the new distribution are given. It is shown that the new distribution is unimodal for all values of its parameters and its hazard rate function or mean residual life function may be constant, decreasing, increasing, bathtub-shaped, or upside-down bathtub-shaped.