• K 0.5 V 2 O 5 /NaV 3 O 8 (KNaVO) performs prominent zinc storage ability. • An efficient dual-phase strategy to synthesize heterogeneous KNaVO hybrid cathode. • The quasi-solid-state ZIBs show excellent flexibility and long cycle capability. Rechargeable aqueous zinc-ion batteries (ZIBs) are promising candidates in energy storage because of intrinsic safety, low-cost and eco-friendliness. However, restricted by cathode materials, ZIBs usually exhibit inferior capacity and limited cycling performance. Herein, an efficient dual-phase strategy is employed to fabricate novel heterogeneous K 0.5 V 2 O 5 /NaV 3 O 8 (KNaVO) hybrid cathode. In traditional aqueous batteries, the hybrid persistently offers long lifespan zinc-ions storage with reversible capacity of 150 mAh g −1 up to 5500 at 5 A g −1 , and impressive rate performance with 128.7 mAh g −1 even at 10 A g −1 due to the ameliorated conductivity and conspicuous pseudocapacitance effect. In quasi-solid-state batteries, the flexible ZIBs can well withstand large-angle deformation from 30° to 120°. And at a large bend angle, ZIBs harvest the considerable capacity of 138.4 mAh g −1 after 1050 cycles at 1 A g −1 due to robust mechanical strength of gel electrolyte and enhanced Zn-storage of dual-phase structured KNaVO. This will be a prospect of applying flexible quasi-solid-state ZIBs in portable and wearable electronics.