The mobile ad‐hoc network is well studied on the routing issues, and the security constraints around achieving higher quality of service (QoS) values are well analyzed. The main task is to establish the path to the target with reliable intermediate nodes based on quality parameters because of the lack of node mobility and central management. In a multi‐constrained QoS issuance, more than the QoS requirements must be satisfied at the end of the application. There are several secure routing protocols available to improve the QoS of Manet by routing packets securely. However, they do not meet the performance requirements. To solve this problem, and efficient Multi‐Constrained Network Feature Approximation (MCNFA) technique is proposed based on safe routing. The method first determines the list of paths between source and destination. According to that, the method approximates the congestion, latency, and hop count values for each route. According to the value obtained in approximation of various parameters, the legitimate weight is computed for all the routes towards the destination. According to the value of the legitimate weight, a single route is selected to perform data transmission. The MCNFA approach improves the routing performance and increases the throughput ratio and other QoS factors. The performance of the proposed method will be assessed using NS2 simulation. The results show that the proposed scheme can maintain a longer network lifecycle in tight scenarios suitable for delay‐tolerant networking. The performance is compared with energy recognition and MCNFA technique‐based energy‐saving routing protocols in various QoS scenarios.