The invention relates to a rapid loop closing calibrating method of a distributing line based on data fusion. The method comprises the following steps: tracing power supply points; calculating the phase difference between alternating voltages on two sides of a loop closing point switch; judging whether the phase difference meets a loop closing condition or not; calculating a loop current; calculating steady-state currents of two to-be-calibrated lines; judging whether the steady-state currents meet the loop closing condition or not; determining the power supply points of the to-be-calibrated lines by means of an electric wiring diagram and a switch state of an EMS system, calculating the phase offset in a power transformation path process, and judging whether the phase offset meets the phase difference requirement or not; and calculating the loop closed ring current by means of equipment parameters of a dispatching automatic system (EMS) and a distribution automation system (DAS), and judging whether a current limiting condition is met or not by combining real-time current data of the DAS system. According to the method provided by the invention, limiting conditions of many aspects can be fully covered by reading information of a power grid topological structure, equipment parameters, real-time data and the like in EMS and DAS, so that rapid, flexible and relatively accurate loop closing calibration of the distributing line are realized.