A resistive memory and a data writing method for a resistive memory cell thereof are provided. The method includes: receiving and decoding a column address signal for generating a decoded result, and providing a word line voltage to a word line of the resistive memory cell; providing a constant current to one of a bit line and a source line of the resistive memory cell, and coupling a reference ground voltage to another one of the bit line and the source line of the resistive memory cell.