A storage device including a cell array and a disturb-free circuit is provided. The cell array includes a first cell and a second cell. The first cell is coupled to a first conductive line and a specific conductive line. The second cell is coupled to a second conductive line and the specific conductive line. The disturb-free circuit performs a first write operation on the first cell and performs a verification operation on the second cell. The verification operation determines whether data stored in the second cell is disturbed by the first write operation. In response to the data stored in the second cell being disturbed by the first write operation, the disturb-free circuit performs a second write operation.