A new multi-control Toffoli(MCT) gate exchange rule is proposed in reversible MCT circuits. Reduction and moving rules of MCT gate sequence are given based on the proposed rule, and a more general reversible MCT circuit simplification algorithm is realized. Effectiveness of the simplification algorithm is verified by specific examples and experimental results of all three variables reversible functions, and it can further reduce the gate number and quantum cost of the reversible circuit. Compared with the existing similar rules, the proposed MCT gate exchange rule has no constraint conditions, and it has stronger applicability, which improves the simplification results of reversible MCT circuits.