A preliminary field identification guide to the main fishes caught by toothfish longline boats fishing in the Ross Sea was prepared under the New Zealand Ministry of Fisheries Project ANT2005-02 and was used by Ministry of Fisheries observers and fishers during the 2006–07 season. That guide was revised in 2007 following comments and suggestions from the users and now covers 27 taxa. Mostly it provides information for identification to species but for liparids (snailfishes), zoarcids (eelpouts) and bathydraconids (dragonfishes) identification is at family level and for Muraenolepis (eel cods), and Pogonophryne (plunderfishes) identification is to genus. Identification to species for some fishes is difficult because of uncertain taxonomic status, e.g., Pogonophryne, or scarcity of field characters, e.g., liparids. Some species likely to be seen only in stomach contents of other fishes are included. Future revisions could be made as taxonomic issues are resolved, and more species are recorded from the Ross Sea. Data and images are stored on a relational database to facilitate revision and easy information retrieval.