Abstract: Whether sedimentary syn-genetic initial enrichment, exhalative-sedimentary mineralization or hydrothermal-sedimentary mineralization occurred in the Yangla Cu Deposit, northwestern Yunnan, has long been a controversial key scientific proposition in the field of mineral deposit geology. Based on regional geological surveys, this study takes the metamorphic clastic rocks of the ore-bearing strata in the deposit as the research object, and conducts systematic investigations including petrology, lithofacies analysis, detrital zircon U-Pb geochronology and detrital component statistics. The results indicate that the metamorphic clastic rocks of the ore-bearing strata are dominated by feldspathic quartz sandstone-feldspathic sandstone with minor volcanic clastics, showing medium compositional maturity. Statistical analysis of detrital components reveals that the provenance was characterized by a transition from stable craton to recycled orogenic belt. The detrital zircon U-Pb ages are 365~2557 Ma, among which the weighted mean ages of the youngest peaks are 368.7±5.6 Ma and 365.1±2.4 Ma, respectively. Combined with previous studies, it is proposed that the ore-bearing strata were deposited during the Late Devonian to Early Carboniferous, which is basically consistent with the constraints from paleontological stratigraphy. The zircon age spectrum (1760 Ma and 2557 Ma of the Paleoproterozoic, 1484 Ma and 1532 Ma of the Mesoproterozoic, 430 Ma and 365 Ma of the Middle Paleozoic) is consistent with that of the Northern Qiangtang-Changdu Block. It is thus inferred that this block served as the sediment provenance of the ore-bearing strata in the Yangla Cu Deposit. The ore-bearing strata were formed in a shallow marine platform environment on the stable continental margin of a Red Sea-type intercontinental ocean basin during the "rifting-expansion" evolution stage of the Jinshajiang Paleo-Tethys Ocean, which provides the tectonic prerequisite for hydrothermal sedimentary mineralization. Furthermore, this study confirms that the Jinshajiang Ocean Basin had already opened by the Late Devonian-Early Carboniferous, and the provenance differences between the two sides of the basin were isolated by the ocean basin itself.