The Proto-Tethys Ocean in the Eastern Kunlun region underwent an Early Paleozoic subduction-orogenic evolution. However, significant controversy remains regarding key geological processes such as subduction and collisional orogeny. A suite of Middle Silurian rapakivi granite and hornblende gabbro assemblages was discovered in the Qimantag area of the Eastern Kunlun. This study presents petrological, whole-rock geochemical, LA-MC-ICP-MS zircon U-Pb geochronological, and Sr-Nd-Pb isotopic analyses of these rocks. The zircon U-Pb ages of the rapakivi granite and hornblende gabbro are 430.1 ± 1.1 Ma and 430.5 ± 1.2 Ma, respectively.Whole-rock geochemical analyses show that the rapakivi granite has high K?O + Na?O content and TFeO/MgO ratios, but low MgO and CaO contents. It belongs to the metaluminous to weakly peraluminous granite series and the shoshonitic series. It is relatively enriched in light rare earth elements (LREEs) and large-ion lithophile elements (LILEs), but significantly depleted in high-field-strength elements (HFSEs), and exhibits a negative Eu anomaly. It has relatively high \[n(87Sr)/n(86Sr)\]i values (0.709000~0.723957) and negative εNd(t) values (-4.82~-5.89). The depleted mantle model age TDM2 ranges from 1559 to 1646 Ma. These characteristics classify it as A-type granite.The hornblende gabbro belongs to the low-K (tholeiitic) series. It is enriched in LILEs but depleted in HFSEs. It also exhibits high \[n(87Sr)/n(86Sr)\]i values (0.709000–0.723957), negative εNd(t) values (-4.82 to -5.89), and TDM2 ages of 1646–1559 Ma.The rapakivi granite and hornblende gabbro originated from distinct magma sources. The rapakivi granite primarily formed by partial melting of Paleoproterozoic felsic crust under low-pressure and high-temperature conditions. The magma source for the hornblende gabbro was the mantle wedge above the subducting slab, which had been metasomatized by subduction-derived fluids.Consequently, it is inferred that northward subduction of the Proto-Tethys Ocean initiated in the mid-Cambrian and persisted beyond 430 Ma. The Eastern Kunlun region was predominantly in a collisional orogenic stage from 428 Ma to 423 Ma, transitioning to an uplift stage from 423 Ma to 406 Ma. Around 430 Ma, the Eastern Kunlun region was in an extensional tectonic setting associated with subduction-rollback.