To improve the development of coordinate measuring machine ( CMM) and the whole machine accuracy design level, a CMM accuracy assignment method based on interval hierarchical analysis is proposed. First, the CMM quasi-rigid body model is formulated. Based on CMM target accuracy and travel range, full-parameter, high-precision solution of the quasi-rigid body model using the least absolute shrinkage and selection operator ( LASSO) and orthogonal trigonometric decomposition, the 21 geometric errors of the CMM are achieved. Then, according to the CMM structure and movement, the accuracy hierarchy of the CMM whole machine is divided. The interval hierarchical analysis is used to determine the accuracy assignment weight vector of CMM critical parts relative to geometric errors. The accuracy assignment results of CMM key components are obtained by using the CMM with the 21 geometric errors and the accuracy assignment weight vector. The results show that, for a CMM with a target accuracy of (4. 5+L / 400) μm, the prototype assembled using the proposed accuracy allocation method achieves an accuracy of (2. 7+L / 400) μm. Therefore, the proposed CMM accuracy allocation method can provide a more accurate basis for the accuracy selection of key CMM components. The accuracy of the whole machine is improved, the efficiency of the whole machine design is saved, and the research and development cost are reduced.