In mobile ad hoc networks, each host moves in an arbitrary manner and thus routes are subject to frequent disconnections. Furthermore, rebuilding routes operations consume lots of the network resources and the nodes energy. In this paper, a novel reliable routing algorithm using fuzzy applicability is proposed to increase the route reliability and reduce the number of broken routes during the routing selection. The algorithm uses fuzzy applicability to express the matching degree between each neighboring node. It produces a routing sprouting tree from source node to destination node utilizing the IRS (immediate reachable set) and RS (reachable set) of each node. Finally, by comparing the applicability of each route in the routing sprouting tree, the most proper route can be computed. The algorithm provides not only a select mechanism for searching the next routing node, but also a global reliability for the whole selected route. The simulation results show that the algorithm can reduce the number of broken routes efficiently when applying the proposed algorithm to the AODV (Ad hoc On Demand Distance Vector) routing protocol.