Herein, we report the design and synthesis of a unique honeycomb-like Ni3S2 structure growing directly on the Ni foam skeleton (H-Ni3S2/NF) and its application in lithium-oxygen (Li-O2) batteries as a free-standing cathode. Excellent electrocatalytic activity of honeycomb-like Ni3S2 and the unique network structure of Ni matrix can provide synergistic effect for facilitating electron transport and the diffusion of both oxygen and Li+, leading to the excellent electrochemical performance of Li-O2 battery. Specifically, Li-O2 batteries with H-Ni3S2/NF electrodes exhibit high energy efficiency (84.2%), outstanding cycle stability of over 116 cycles at limiting capacity of 4 mA h cm−2 and excellent rate capability (9.84 mAh cm−2 at 12 mA cm−2).