Male waving displays of the species of Ilyoplax (Brachyura: Ocypodidae) have so far been described in I. delsmani, I. gangetica, and I. orientalis. In this study, male waving displays of I. dentata, I. dentimerosa, I. deschampsi, I. formosensis, I. integra, I. ningpoensis, I. pingi, I. pusilla, I. serrata, I. strigicarpa, I. tansuiensis, and Ilyoplax sp. are described for the first time. Waving display of the above 15 species of Ilyoplax can be classified into three patterns; a circular type, vertical type, and asymmetrical type. Asymmetrical wave forms were observed in only two species, I. orientalis and I. tansuiensis, vertical wave forms were seen in four species, I. delsmani, I. dentimerosa, I. pingi, and I. serrata, while most other species exhibited circular wave forms. To understand the evolutionary divergence of these waving forms observed in species of Ilyoplax, a molecular phylogeny was reconstructed based on 1005-bp nucleotide sequences from mitochondrial 16S and 12S rRNA genes of 16 species and two out-group taxa. Phylogenetic analysis of waving forms suggested that circular waves evolved once in the early history of the lineage. Vertical wave forms were suggested to have subsequently evolved three times independently from circular wave forms, and the asymmetrical wave form has also evolved from circular wave form. The evolution of distinct waving forms is considered to be associated with the presence of geographic sympatric species.