A memory device includes a page buffer unit including a plurality of latches latching each of a plurality of pieces of dummy data of selected memory cells according to a plurality of dummy signals provided by a word line of the selected memory cells, and a control logic comparing a count value of a first count latch among the plurality of latches with a reference count value, determining whether to count a second count latch other than the first count latch according to a result of the comparison, and correcting a level of a read signal provided by the word line of the selected memory cells in a read operation.