The novelty of multiple-input multiple-output (MIMO) radar is to improve the performance of radar utilising spatial diversity and waveform diversity. Proposed is the optimisation design of complete complementary sequence (CC-S) for MIMO radar based on channel capacity with the clutter statistical properties known. The method obtains the optimised CC-S through maximising the channel capacity of MIMO radar. The result shows that the optimised CC-S is a function of the clutter covariance matrix. Finally, the method from the information theoretical point of view is verified.