The invention discloses a method, an apparatus and a system for automatically enabling a high-availability function of a virtual machine. The method comprises the steps that a cloud management platform receives a high-availability function enabling application sent by a user through a virtual machine agent apparatus in the virtual machine; the cloud management platform detects whether a virtual host where the virtual machine is located supports the high-availability function or not; and if the virtual host where the virtual machine is located supports the high-availability function, the cloudmanagement platform includes the virtual machine in a heartbeat monitoring list and notifies the virtual machine agent apparatus to start reporting heartbeat information. By initiating the enabling ofthe HA function in the virtual machine, a self-service enabling system framework is provided for the user, so that the user can quickly manage the HA function of the virtual machine as needed, and the problem of resource waste due to default enabling and the problem of process response from business acceptance to a back end are effectively solved.