The rise of Internet of Things (IoT) applications and the widespread use of mobile devices have made Mobile Ad Hoc Networks (MANETs) more important in modern day. Enabling effective data transport in decentralized wireless networks is largely dependent on the routing mechanism. In the present research, Mountain Gazelle Optimizer (MGO) is integrated with Low Energy Adaptive Clustering Hierarchy (LEACH) protocol to offer an effective routing and clustering framework for MANETs. Intelligent approaches are necessary for dependable data transmission and energy conservation in MANETs due to their inherent mobility and dynamic topology changes. To overcome these obstacles, the LEACH protocol is used for energy efficient and adaptive clustering, in which cluster heads are chosen at random to distribute energy usage among nodes. The Mountain Gazelle Optimizer, an evolutionary algorithm modelled after the adaptive movement behavior of gazelles, is used to optimize routing between cluster heads and destination nodes. By reducing parameters like energy usage, transmission latency, and route instability, MGO optimizes the routing paths. When compared to conventional methods, the proposed MGO LEACH model improves Packet Delivery Ratio (PRD) and network lifetime and lowers routing costs. The proposed design greatly enhances MANET’s performance, as shown by extensive simulation findings, which makes it ideal for dynamic and energy constrained wireless network situations.