The invention relates to optical communication technology and provides a method of solving optimum layer rate distribution and optimum wavelength resource distribution in a request protective light multicast switched network. The problem that a traditional multicast max-flow minimum value confirmed layer rate causes heterogeneous network node fairness and low handling capacity is solved. According to the method, a link separation route cluster is found, share degree of the link separation route cluster is calculated, a route inflow node with high share degree adopts network coding information, and information of code compression is transmitted in the route cluster with high share degree, wavelength resources are preferentially distributed to a link with the high share degree, minimum demand distribution of the wavelength resources is achieved, and use ratio of optical network limited wavelength resources is improved. The method of solving optimum layer rate distribution and optimum wavelength resource distribution in the request protective light multicast switched network is in favor of achieving maximum throughput of network, improves wavelength resource use ratio of a light group multicast network, and reduces wavelength number required by a light group.