Yunkai massif is dated by using monazite (EMP and Nano-SIMS) and zircon (LA-ICPMS). Monazite inclusions in the platy minerals exclusively yield Triassic ages. Deformations (NW- and NE-trending) in Yunkai massif occurred at ~ 245 Ma and ~ 230 Ma. South China-Indochina collision and mafic magma emplacement may cause these deformations.