With the increase of network traffic, the complexity of dynamic routing calculation in fiber optic networks increases, consuming more joint resources. Therefore, a joint resource optimal allocation method of Dynamic routing in optical fiber networks is proposed.. Map network nodes in the form of a directed graph to calculate the spectrum utilization of routing transmission. Obtain Dynamic routing joint resources according to bandwidth, delay, and network delay jitter indicators. By selecting the spectrum service with the best continuity through the spectrum continuity of the transmission path, the service is segmented and merged based on spectrum sensing and greedy algorithms to achieve optimal joint resource allocation. Experimental results show that when the traffic load is 400 Erlang, the bandwidth Constrictively of the proposed method is only 10%, and the spectrum utilization rate is as high as 90%. In addition, after a dynamic resource transmission cycle, the proportion of data nodes in this method is low, indicating that this method has good stability.