In mobile ad hoc networks, multipath routing improves end-to-end throughput through parallel transmission on multiple paths, which is affected by path inter-path interference. This paper proposes a routing protocol IBMR (interference- and bandwidth-based multipath routing), which maximizes the available bandwidth of the path between source and destination, and minimizes the interference between the two corresponding paths. Simulation results show that IBMR has a good performance in terms of end-to-end throughput, packet delivery ratio, and delay.