Abstract: To reduce the delay of reversible network, we built delay model of reversible network, and put forward a delay optimization algorithm of reversible network.Reversible network was shown in music line style, the corresponding delay values were accumulated after passing every reversible gate;delay of target output took the maximum value of all output delay of the gate.The proposed optimization algorithm was based on moving and simplification rules of sub-sequence in reversible network.The algorithm scanned reversible network bidirectionally and optimized it when satisfying the delay optimization rules.We can obtain two results according to the scanning direction, and the result with less delay is our last result.The experimental results on all 3-variables reversible functions and some representative examples in the Benchmark show that, the delay in reversible network can be reduced effectively and the cost of reversible network is decreased.