—In this paper, the capacity of multiple input multiple output-orthogonal frequency division multiplexing (MIMOOFDM) systems is analyzed under doubly correlated fading channels. The distribution of complex central Wishart Matrix is utilized to derive the closed form of ergodic capacity of MIMOOFDM systems under doubly correlated channels when the transmitter has no channel state information (CSI) and the receiver has the perfect CSI. Then the obtaining results are used to study the impact of channel correlation on the capacity. The simulation results show that our closed form capacity is close to the real value and that the channel correlation degrades the system capacity. Keywords- MIMO-OFDM; capacity; doubly correlated.