A read sensing method for an OTP non-volatile memory is provided. The memory array is connected with plural bit line pairs. Firstly, the plural bit line pairs are precharged to a precharge voltage. Then, a selected memory cell connected with a specific bit line pair is determined. Then, two bit lines of the specific bit line pair are respectively connected with the data line and the reference line and are discharged to a reset voltage. After a first cell current and a second cell current from the specific bit line pair are received, a first voltage level of the data line and a second voltage level of the reference line are gradually changed from the reset voltage. According to a result of comparing the first voltage level and the second voltage level, an output signal is generated.
