In this paper, an opportunistic cooperative ad hoc sensor network with randomly located nodes is analyzed. The randomness of nodes' locations are captured by a homogeneous poisson point process. The effect of imperfect interference cancellation is also taken into account in the analysis. Based on the theory of stochastic geometry, the outage probability and the cooperative gain are derived. The correctness of the analysis is verified by simulation results. The analytical results can thus serve as a guidance for wireless sensor network design. © 2012 IEEE.