To provide an automatic packing method for automatically performing a packing work of a packaging bag filled with tea leaves which is relatively hard and requires experiences.

This automatic packing method comprises a longitudinal binding step in which the packaging bag S of substantially cylindrical shape filled with tea leaves is bound by winding a band B therearound in the longitudinal direction of a barrel, and a transverse binding step in which the packaging bag S is bound by winding the band B in the circumferential direction of the barrel. The packaging bag S is automatically transferred and attitude-set in a completely unmanned condition between the longitudinal binding step and the transverse binding step.