Developing low Pt loading and high-activity oxygen electrocatalysts is necessary to promote large-scale fuel cell applications. By data-driven and density functional theory calculations, PtFeCoNiMnGa nano high entropy alloy (HEA) was synthesized through liquid-phase reduction and H2 calcination method and loaded on carbon nano-tube (CNT). Due to high entropy, electronic modulation, and cocktail effects, PtFeCoNiMnGa HEA catalyst shows great catalytic activity in oxygen evolution/reduction reaction (OER/ORR). The PtFeCoNiMnGa/CNT showed a low overpotential of 243 mV for OER, and for ORR a mass activity of 1.12 A mgPt−1 (5.3 times than Pt/C). Moreover, the PtFeCoNiMnGa/CNT showed high durability by maintaining 95 % of its initial performance for up to 50 h. In addition, the zinc-air battery assembled with PtFeCoNiMnGa/CNT as the cathode catalyst had an open-circuit potential of 1.52 V and an energy density of 130.6 mW cm−2, and was able to operate stably for 120 h without any significant degradation.