This article addresses the macro-event, a fundamental concept for the Talmyan two-way typology. It proposes a diachronic aspect of macro-event, an aspect that seems to be under-appreciated or even neglected. It argues that a macro-event integrates two simple events through grammaticalization. This hypothesis is supported by the behaviors of directional verbs in Mandarin Chinese in that these forms alone can express almost all five types of macro-events that Talmy analyzed, and that these macro-events themselves represent an integration of two simple events, and exhibit various degrees of grammaticalization. This study relates two seemingly unrelated areas of research, i.e. event structure and grammaticalization and provides a new perspective to the Talmyan typological paradigm.