The present invention relates to a method of programming a nonvolatile memory device. A method of programming a nonvolatile memory device in accordance with an aspect of the present invention can include performing a program operation on a first page, counting a program pulse application number until the program operation on the first page is completed, comparing the counted program pulse application number and a critical value and resetting a program start voltage based on the comparison result, and performing a program operation on a second page using the reset program start voltage.