The present invention relates to the field of data security, and aims to provide a random time based nonvolatile memory data secure erasure method. The method comprises: by using a random number generator, a counter and a high frequency clock structure, regulating and controlling the data erasure time, so that the erasure time is random, the number of residual electrons in the floating gate unit is random, difficulty of data recovery is greatly increased, and data security of the memory chip is guaranteed. Thus, the technical scheme adopted in the present invention is the random time based nonvolatile memory data secure erasure method, and the method specifically comprises the following steps: by using a random number generator, a counter and a high frequency clock structure, controlling the data erasure time, so that the erasure time is random, and the number of residual electrons in the floating gate unit is random. The method disclosed by the present invention is mainly applied to data security.