Genetic and phenotypic data from an East Australian metapopulation of the intertidal goby, Bathygobius cocosensis (Bleeker 1854). Data was collected over three years (2014–2016) from juveniles and adult subpopulations at three sites: Point Cartwright, Hastings Point and Shellharbour. Genetic variation was characterised using genome-wide SNPs, obtained through pooled ezRAD sequencing. Phenotypic variation was characterised using geometric morphometric analysis of head shape morphology. The analyses contained in this repository are for a manuscript submitted to Molecular Ecology.