A data sensing method for sensing data stored in first and second memory cells includes the steps of: setting a first voltage according to a bit-line voltage corresponding to the first memory cell in response to an enabled level of a first clock signal; providing the first voltage as a sensing voltage in response to a disabled level of the first clock signal; comparing the sensing voltage with a reference voltage to generate a first output voltage; setting a second voltage according to a bit-line voltage corresponding to the second memory cell in response to an enabled level of a second clock signal, a phase difference between the first and second clock signals being 180 degrees; providing the second voltage as the sensing voltage in response to a disabled level of the second clock signal; and comparing the sensing voltage with the reference voltage to generate a second output voltage.