Among various catalysts, the mixed valence transition metal oxides have exhibited great importance in applications of energy technologies because of their low cost, facile synthesis, considerable activity, and stability in aqueous alkaline solutions [23; 24; 25; 26]. Notably, catalysts based on Co and Mn have garnered attention for their high bifunctional efficacy in ORR and OER. This largely ascribes to the high oxidation potential of Co and the enhanced electronic transport characteristics of Mn [27; 28; 29]. Nonetheless, the inherently low electronic conductivity of these mixed valence transition metal oxides remains a critical barrier, impeding further enhancements in catalytic performance. The recent innovation in carbon-support materials such as graphene, carbon fibers, and nanotubes, offers promising approaches to overcome this limitation [30; 31]. Consequently, the integration of oxides with nanocarbons significantly amplifies the electrocatalytic activity and stability, a result of the exceptional electronic conductivity, remarkable flexibility, and expansive surface area of carbon-based materials. Furthermore, the fine dispersion of oxide particles and the robust interfacial coupling within these composites are crucial factors driving superior catalytic efficiency [32; 33; 34; 35]. Due to the structural superiority, a series of cobalt-manganese mixed oxides have been explored, such as Mn\({}_{x}\)Co\({}_{3x}\)O\({}_{4}\), MnCoO\({}_{x}\), and CoMn\({}_{2}\)O\({}_{4}\) systems [36; 37]. However, the majority of previous work leaned towards the applications for anode materials, supercapacitor, and ORR electrocatalysts. Hence, developing the kind of nanocomposite catalysts with bi-functional electrocatalysis still remains a great challenge [38; 39]. In this work, we have adeptly synthesized uniform MnCo\({}_{2}\)O\({}_{4}\) and CoMn\({}_{2}\)O\({}_{4}\) nanoparticles of reduced size, composed primarily of non-precious metals, seamlessly anchored onto carbon nanotubes (CNTs) using a straightforward, surfactant-free, two-step process with superior performance compared to Pt/C at a low price. We evaluated the catalytic efficiency of MnCo\({}_{2}\)O\({}_{4}\)-CNTs and CoMn\({}_{2}\)O\({}_{4}\)-CNTs towards ORR and OER. When contrasted with pure manganese cobalt oxide nanoparticles, the activity of the composites integrated with CNTs is markedly enhanced. Notably, the MnCo\({}_{2}\)O\({}_{4}\)-CNTs nanocomposites outshine all other prepared samples in ORR performance, displaying activity comparable to, and durability surpassing, that of the conventional Pt/C catalyst. Additionally, MnCo\({}_{2}\)O\({}_{4}\)-CNTs demonstrate a more pronounced positive onset potential, superior current density, and enhanced durability compared to the mere physical mixtures of MnCo\({}_{2}\)O\({}_{4}\) and CNTs (MnCo\({}_{2}\)O\({}_{4}\) + CNTs). This improvement is largely ascribed to the strengthened chemical bonding between MnCo\({}_{2}\)O\({}_{4}\) and CNTs [40]. Furthermore, MnCo\({}_{2}\)O\({}_{4}\)-CNTs also exhibit significant catalytic performance in OER, positioning them as a formidable contender for bifunctional catalysts in the domain of energy conversion and storage.