In this work we propose a method for organizing multipath routing for SDN networks. It have two main parts. The fisrt one is a routing method based on modified wave algorithm for finding paths, and second one is load balancing method based on ECMP algorithm. Combination of these methods can optimize using of network resources and provide a more optimal load balancing of network. The basis of routing algorithm is the search and use partially-overlapping routes. The basis of load balancing algorithm is equal distribution network load between all found routes. A comparative analysis with an existing algorithms for routing and load balancing was conducted and the advantages of this development are presented.