A program method of a storage device which includes at least one nonvolatile memory device and a memory controller to control the at least one nonvolatile memory device, the program method comprising: performing a first normal program operation to store first user data in a memory block; detecting, at the memory controller, a first event; performing a dummy program operation to store dummy data in at least one page of the memory block in response to the detection of the first event; and performing a second normal program operation to store second user data in the memory block after the dummy program operation, dummy program operations being operations in which random data is programmed into the memory block, normal program operations being operations in which data other than random data is programmed in the memory block.