An electronic device, and an over-erase detection and elimination method for memory cells are provided; the method includes: performing an erase operation on a specified area; selecting all the memory cells in the selected area one by one; measuring a threshold voltage of a selected memory cell for over-erase detection to see if it is less than a normal erase threshold voltage; if not, selecting the next memory cell for over-erase detection, and if yes, then performing a soft-write operation on the selected memory cell; after the soft-write operation, performing over-erase detection again to see whether the threshold voltage of the selected memory cell is within a normal threshold range; and if not, performing a soft-write operation again, and if yes, the next memory cell is selected for over-erase detection, until the threshold voltages of all the memory cells selected for erasure are within the normal threshold range.