The development of genome editing techniques based on CRISPR (Clustered regularly interspaced short palindromic repeats)-Cas9 system has revolutionized biomedical researches. It can be utilized to edit genome sequence in almost any organisms including Caenorhabditis elegans, one of the most convenient and classic genetic model animal. The application of CRISPR-Cas9 mediated genome editing in C. elegans promotes the functional analysis of gene and protein under many physiological conditions. In this mini-review, we summarize the development of CRISPR-Cas9-based genome editing in C. elegans.