A new dynamic routing algorithm based on the blocking nodes was presented for the wavelength routing optical networks(WRON) consisting of partial-shared wavelength converter(PWC).Instead of sharing the complicated information of wavelength converting,it takes the blocking characteristics of each node into consideration in the routing process.To estimate the algorithm,we do the emulation in the 14-nodes national science fund network(NSFNET).The result shows that the performance of the blocking probability as well as the probability of setting up failure has been improved greatly and can be improved even greater when the network is in low load.