Since performance of equal gain combination (EGC) over correlated Nakagami fading channels does not have exact closed-form expressions, efficient approximation based on moment matching is proposed in this paper. We approximate the superposed fading distribution of EGC output by a new −μ distribution. Thus the system performances can easily be obtained with the aid of stochastic properties of the −μ random variable. The performances include signal-to-noise ratio (SNR) distribution, outage probability and average error ratio (SER). The method is easy to implement, and the simulation results match the theoretical ones very well. It can be applied to parameter design and performance evaluation of EGC system over various fading channels.