To improve the retrieval accuracy of cloud macro-physical parameters （cloud base height， CBH； cloud top height， CTH； cloud thickness， CTK；and cloud layer number，CLN） over the plateau area using millimeter-wave radar （MMCR） measurements， this study proposed an improved retrieval method. Differences between MMCR- and ceilometer CL31- derived CBHs， and between MMCR- and Himawari-8（HW8）- retrieved CTHs were analyzed. The vertical distribution and diurnal variation of clouds over the Nagqu of Tibetan Plateau in summer observed by these three instruments were also investigated and compared in detail. Results indicate that the presented method can avoid the influences of range sidelobe and cloud layer misclassification compared with the previous method. MMCR-derived CBHs and CTHs are both higher than the counterparts of CL31 and HW8， respectively. Whereas， their vertical distributions and diurnal variations are significantly coherent. The MMCR has a better performance on the CBH observation of multiple-layered clouds than CL31， and similarly can obtain more accuracy measurements of CTHs than HW8. The radar sidelobe echo has apparent influences on the retrievals of cloud macro-physical parameters for both different cloud types.