A method of reading data in a non-volatile memory device compensates for a change in a reading/verifying result in accordance with a change of temperature. The method includes sensing a temperature of memory cells, setting a first voltage and a second voltage of a bit line sensing signal in accordance with the sensed temperature, precharging a bit line in accordance with the set first voltage, evaluating a change of a voltage level of the bit line based on whether a memory cell for a read operation is programmed, and sensing data of the memory cell in accordance with the set second voltage. The method may read/verify data constantly even though a temperature is changed.