The Grass Emperor (Lethrinus laticaudatus) is distributed across northern Australia, including the Great Barrier Reef, Coral Sea, and Western Australia, and occurs more broadly throughout the Indo-West Pacific. It typically inhabits sandy or rubble areas near coral reefs, lagoons, and coastal slopes. This assembly was produced by Ocean Genomes. It is based on PacBio HiFi long reads, Dovetail Omni-C libraries, and Illumina short reads. Data was generated at the Minderoo OceanOmics Centre at the University of Western Australia and assembled in house using a custom pipeline (https://github.com/Computational-Biology-OceanOmics) that follows Vertebrate Genomes Project workflows (https://vertebrategenomesproject.org/). The raw data and version 1 assembly are made available and should be credited in accordance with Ocean Genomes data use and sharing policies URL: https://www.minderoo.org/oceanomics. To discuss interim access, please contact oceangenomes@uwa.edu.au.