This paper presents the geochronology of zircon SHRIMP U-Pb and muscovite laser ⁴⁰Ar/³⁹Ar dating on the leucogranite from Malashan dome in Northern Himalaya, Gyirong. The U-Pb ages of the leucogranite show that the magmatism (anatexis and emplacement) of leucogranite in core of the dome took place since ~30 Ma to ~17 Ma. The youngest U-Pb age of ~17 Ma and the muscovite ⁴⁰Ar^/39Ar ages of 17~15 Ma indicate the latest magmatic emplacement and the possible event of doming and cooling. The youngest U-Pb age and the ⁴⁰Ar/³⁹Ar ages (17~15 Ma) represents the diapirism and doming of the Malashan dome. The tectonic regime following that time may give the way to the east-west extension (beginning since ~13 Ma).