Abstract: The black hole barrier penetration time in a curved space time is discussed.By supposing that the tunneling process is an instantaneous process,we get an emission spectrum of massive particles with the WKB approximation method.This spectrum denotes that the emission of the massive particle near the horizon satisfies the unitary theory in the quantum theory,and supports Parikh-Wilczek＇s conclusion.It is seen from reasonableness of our result that the quantum tunneling in the event horizon of a black hole should be an instantaneous process.

Key words: curved spacetime, barrier penetration time, Hawking radiation, black hole