A data write-in method and a non-volatile memory are provided. The data write-in method includes: providing a reset voltage to a plurality of selected memory cells according to a first flag, and recursively performing a reset process for the plurality of selected memory cells; setting a second flag according to a plurality of first verification currents of the plurality of selected memory cells; and under a condition that the second flag is set: providing a set voltage to the plurality of selected memory cells according to a resistance of the plurality of selected memory cells; and setting the first flag according to a plurality of second verification currents of the plurality of selected memory cells.