In this work, the effect of boron content (CB) on the diffusion of hydrogen has been investigated in the ordered Ni3Fe alloy by using the methods of the cathodic charging hydrogen and vacuum stretching. It can be found that the diffusion coefficient of hydrogen decreases while the diffusion activation energy increases with the increase of boron content when CB≤0.06 wt%. The diffusion coefficient of hydrogen is subject to negligible changes and the diffusion activation energy decreases slightly when CB > 0.06 wt %. The atom probe chromatography reveals the segregation of boron atoms at grain boundaries in ordered Ni3Fe alloys. Through the comparative study of the effect of boron content on hydrogen diffusion coefficient and hydrogen embrittlement factor, it is confirmed that boron atom could reduce the hydrogen embrittlement sensitivity of ordered Ni3Fe alloy in hydrogen environment with the reason of reducing the intergranular diffusion coefficient of hydrogen by boron atom in the alloy.