A memory system includes a nonvolatile memory device and a controller. The nonvolatile memory device includes a memory block including a plurality of memory cells, a first memory region of memory cells coupled to a first word line and a second memory region of memory cells coupled to a second word line. The controller performs a single level cell (SLC) program operation on the second memory region and perform a fine program operation on the first memory region after a completion of the SLC program operation on the second memory region.