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The Longyou garnet-bearing amphibolite, located in the Cathaysia block, has received much attention as it has important implications for the early Paleozoic tectonic evolution of the Cathaysia block and the South China block. The controversy over whether the amphibolite is a retrograde eclogite has been boosted by recent studies. Pseudosection modeling defines the peak <i>P&#8722;T</i> conditions of ~0.9 GPa and 770 &#176;C and a clockwise <i>P&#8722;T</i> path from epidote-amphibolite facies to garnet-amphibolite facies followed by an overprinting greenschist facies retrogression. Geochemical analyses suggest the amphibolite has an enriched mid-ocean ridge basalt (E-MORB) affinity. The Lu-Hf and Sm-Nd garnet dates of 401.7 &#177; 1.4 Ma and 331.4 &#177; 4.5 Ma reflect the difference in closure temperature and thus a subsequent slow cooling process. The spread zircon U-Pb dates from ca. 465 to 416 Ma reflect zircon crystallization during prograde to near peak metamorphism. The U-Pb dates of the adjoining schist suggest contemporaneous metamorphism with amphibolite. These data indicate that the Longyou garnet amphibolite is not an exotic rock nor a retrograded collision-related eclogite, rather that it is related to prolonged burial and long-term residence at high-temperature/medium-pressure conditions followed by a slow cooling process after peak metamorphism.