A storage device may perform a reprogram operation on a page on which a program operation is interrupted due to a sudden power off. The storage device may include a memory device including a plurality of memory blocks, each of which includes a plurality of pages, and a memory controller configured to perform a reprogram operation on a page in which a program operation is suspended using reprogram data that is set depending on threshold voltages of memory cells included in the page on which the program operation is interrupted, among the plurality of pages.