Abstract: Detrital zircon U‐Pb dating and Hf isotope analysis have been evidenced to be effective for reconstructing paleography and tectonic evolution of different continental blocks/terranes. Our new  detrital zircon U‐Pb and Hf isotopic results combined with literature data for the Paleozoic (meta)  sedimentary rocks in the Baoshan and Lincang Blocks provide crucial constraints on the paleogeographic  position and tectonic affifinity of these blocks during Paleozoic times. The Lincang and Baoshan Blocks  were linked with each other during Early Paleozoic times, located on the northern margins of Australia and  India in Gondwana, respectively. But a rift‐related ocean basin could likely have existed between these  two blocks although they were still attached to East Gondwana during Middle Devonian‐Early Permian  times. In contrast, the Simao‐Indochina Block had rifted from East Gondwana at least before the Late  Ordovician as reflflected by their young age cluster at ~450 Ma that is distinct from the characteristic  Pan‐African event (600–520 Ma) in Gondwana. Therefore, the Lincang Block did not represent a continental  arc of the Simao Block before the Early Permian, but rather it rifted from the northern margin of  Australia Gondwana in the Early Permian and subsequently as an independent block drifted northward  to the west side of the Simao Block. Taken together, we propose that the Changning‐Menglian Tethys Ocean  was a long‐lived ocean developing successively at least from the Late Ordovician to the Permian and that  the southern continuation of the Lincang Block is the Inthanon zone rather than the Sukhothai zone.