Abstract: In Heideggers philosophy， the performance of technology consists of three layers—the instrumental stipulation of technology， the stipulation of technology as machination and the essence of technology， i.e.， Gestell. The connotations of technology in Heideggers philosophy should be understood taking his ontology as the perspective. In his view， being is specifically manifested by three segments， namely， being in metaphysics， being in the first beginning and being in another beginning. Only by taking Heideggers ontology as the background and the connotations of technology as a type of being in metaphysics， the internal relationships among these three layers could be revealed， the connotations of technology could be understood as a whole， and the significance of technology as the kehre of being could be clarified.

Key words: Heidegger, being, technology, presence