The invention relates to a rapid current differential protection method based on a recursive Fourier algorithm. The method comprises the following steps: calculating a current phasor of a power transmission line by use of the recursive Fourier algorithm; calculating a current abrupt change amount after a fault occurs in the power transmission line by use of the recursive Fourier algorithm; according to the current phasor and the abrupt change amount of the current phasor, constructing respective current differential protection criteria; and when one of the current differential protection criteria is satisfied, performing protective motion. According to the technical scheme provided by the invention, the influences exerted by a data window on the rapidness and sensitivity of current differential protection are overcome, and the motion speed of the current differential protection is substantially improved.