A read sensing method for an OTP non-volatile memory is provided. The memory array is connected with plural bit lines. Firstly, a selected memory cell of the memory array is determined, wherein one of the plural bit lines connected with the selected memory cell is a selected bit line and the other bit lines are unselected bit lines. Then, the unselected bit lines are precharged to a precharge voltage. Then, the selected bit line is connected with the data line, and the data line is discharged to a reset voltage. After a cell current from the selected memory cell is received, a voltage level of the data line is gradually changed from the reset voltage. According to at least one result of comparing a voltage level of the data line with a comparing voltage, an output signal is generated.