Two alkaline plutons occurred in the eastern part of Guyang County, Inner Mongolia. Recent Isotopic chronology study shows that two alkaline plutons formed respectively at the Early Mesoproterozoic and Early (-Middle) Devonian, the zircon SHRIMP U-Pb age of the Wayao quartz-syenite indicate the quartz-syenite similar to the aluminous A-type granite and derived from the partial melting of upper crust under extensional tectonic setting. The Mesoproterozoic alkaline intrusion belt indicates the rifting event after assembly of North China Craton at Late-Paleoproterozoic, the one of Early (-Middle) Devonian implies the post-collisional extension event after the Early-Paleozoic arc-continental collision in the northern margin of North China Craton