The crystallization process of metallic glass Zr65Al7.5Ni10Cu17.5 (atom fraction in %) were studied by transmissionelectron microscopy and X-ray diffraction. Two stages of crystallization process, which are indicated by the two exothermicpeaks in the differential scanning calorimetry diagram, were studied separately. It is found that the phases in the variousstage of the crystallization are different. In the first stage, it consists mainly of tI-CuZr2 and tP-Al2Zr3 phases, between whicha definite orientation relationship is found. While in the second stage, in addition to the above phases, phase hP2-Al2NiZr6and phase hp3-α-Zr appear, between which another orientation relationship is also found. At the same time, a comparison ismade based on the study of the phases exist in the arc-melted master ingot. The lattice parameters of the identified phaseswere determined and some interesting similarities were found. According to these similarities, all the phases were classifiedinto two groups. The first is: oB, tI-CuZr2, and hp3-α-Zr, the other is: hP2, tP-Al2Zr3 and hp1-Al2NiZr6. The relationshipsbetween phases in these two groups were investigated and the probable reasons that may result in these relationships werediscussed.