Ailaoshan tectonic belt is located at the boundary between the Yangtze and Indochina Plates in Yunnan province, exhibits a controversial tectonic attribution for its Precambrian geological record. The Pingbian Group is one of the most significant Precambrian metamorphic sedimentary strata in Ailaoshan tectonic belt. Clarifying the provenance information of the metamorphic sediments of the Pingbian Group is crucial for understanding the tectonic affiliation of the Precambrian geological record in Ailaoshan tectonic belt. Based on the U-Pb age and Lu-Hf isotope data of detrital zircons of Pingbian Group, investigates the oldest sedimentary age, provenance, and regional tectonic implications by analyzing the source of detrital zircons from different age groups. The results show that based on the youngest five magmatic detrital zircons, the sedimentary age of the Pingbian Group is not older than the late Neoproterozoic (~565 Ma), rather than the previously assumed mid-Neoproterozoic. Zircon U-Pb ages and εHf(t) values of different ages have a large distribution range, indicating that the provenance region of Pingbian Group is strongly polygenic, and the characteristic age peaks of ~0.8 Ga and ~1.8 Ga are consistent with the contemporaneous sedimentary records of the western margin of the Yangtze. It is suggesting that the western Yangtze margin was the primary source area for the detrital material of the Pingbian Group. Furthermore, the consistency of the zircon age spectra of early Paleozoic clastic sedimentary rocks east of Ailaoshan-Tengtiaohe fault within the Ailaoshan tectonic belt further demonstrates that, from the late Precambrian to the early Paleozoic, the region continuously received material contributions from the western Yangtze margin. Therefore, the area from the Tengtiaohe fault eastward to Pingbian in the Ailao Shan tectonic belt is considered an extension of the southwestern margin of the Yangtze Block.