The invention discloses a comprehensive protection method and device of a direct current collection cable, and relates to the technical field of fault protection of a direct current collection grid-connected system. The method can inhibit the fault current and accurately position the direct current cable fault position. The method mainly comprises the steps that a direct current capacitor discharging equivalent circuit of the starting end or terminal end of the direct current cable is built, wherein the equivalent circuit comprises series connection current limiting reactors used by the method; according to the capacitor discharging equivalent circuit and protection constraint conditions, the reactance parameter values of the current limiting reactors are calculated; the current limiting reactors with the reactance parameter values are connected in series in the direct current cable; the voltage values on the current limiting reactors connected in series in the direct current cable areobtained; according to the voltage values of the current limiting reactors, the fault types of the direct current cable are judged, wherein the fault types include a positive electrode fault, a negative electrode fault and an interelectrode fault; according to the fault types, the position of fault points is calculated and positioned. The method and the device are mainly applied to fault protection and fault positioning of the direct current cable in new energy source direct current collection networks and other direct current power transmission and power distribution networks.