Method for one number connecting calling method and service control point

A one-number-service calling method is provided. The method includes: a service control point receives a call in a circuit bearing domain initiated by a calling terminal; the service control point judges whether the call is required to be anchored to an IP multimedia sub-system domain for processing according to an online state of an association number of a called terminal of the call; if so, the call is anchored to the IP multimedia sub-system domain for processing; if not, the call is initiated to the called terminal, and the call between the calling terminal and the called terminal is connected. A service control point for one-number-service calling is also provided. The solution reduces the unnecessary anchoring process, consequently reduces the call delay, is more conforming to the usage of the user, and provides the better service experience to the user.