Because of the high hydrogen permeability and high resistance to hydrogen embrittlement of Pd-based alloys, Pd-Ag alloys have been used as hydrogen permeation membranes for separation and purification of hydrogen gas. However, Pd is too expensive for large-scale industrial applications as hydrogen permeation membranes. The development of alternative membrane materials with higher hydrogen purification efficiency and lower cost is therefore strongly desired. From the viewpoint of the hydrogen permeability, some bcc metals such as Nb, V and Ta are promising candidates since their predicted hydrogen permeability are larger than that of Pd. Nb-Ti-Co ternary alloy has been considered as the best candidate because of lower cost, good thermal stability, the high hydrogen permeability and high resistance to hydrogen embrittlement. In this work, the eutectic composition in Nb-Ti-Co alloy was probed and verified through Bridgman directional solidification experiment. Microstructures, hydrogen permeation properties and hydrogen embrittlement of near eutectic Nb-Ti-Co alloy were investigated and compared with those of pure Pd. The results indicate that the eutectic composition in Nb-Ti-Co alloy is Nb₃₁Ti₃₅Co₃₄, and its solidification microstructures contain only the Nb(Ti, Co) and TiCo phase, which shows regular coupled growth by Bridgman directional solidification at the rate of 5 μm/s. The eutectic alloy shows the higher hydrogen permeability of 2.7×10^-8 mol/(m·s·Pa^0.5) at 673.5 K, which is 1.72 times higher than that of Pd alloy. The hydrogen permeability decreases with the decrease of Ti/Co ratio at the same Nb content. A slight crack first appears in the TiCo phase, which is the source of cracks in the membrane, and then the cracks propagate along the edge of the membrane. When the volume fraction of TiCo phase is less than 5%, the eutectic Nb(Ti, Co)+TiCo phases may offset the crack in the TiCo phase, thus the membrane exhibits large resistance to the hydrogen embrittlement.