Today, establishing a reliable communication path between devices in low power and lossy networks (LLNs) has become a big challenge. Routing protocol for low power and lossy networks (RPL) is used as a standard routing protocol in LLN networks. The RPL protocol, located at the network layer, uses the objective function to select the optimal path. Due to the fact that various attacks may be created in the routing process, hence the need to pay attention to reliable and trusted routing has become one of the most important and up-to-date research issues. For this reason, in this research, a reliable routing method based on RPL for the Internet of Things is presented. The advantages of the proposed method compared to other methods are that, on the one hand, the rate of lost packets has decreased, and on the other hand, the stability of a node is higher in relation to rank changes. Finally, Cooja simulator has been used to evaluate the proposed method.