Length-weight relationships (LWRs) of six fish species in the Southern Ocean, which commonly associated with Antarctic krill fishery, were determined. Samples were collected with Chinese krill trawler (codend mesh size 2 cm) in the Atlantic sector of the Southern Ocean from January to August 2016. Data on LWRs and the relationships between standard length and total length of those species were presented. Those data on fish species derived from Antarctic krill fishery will be very helpful in understanding the interaction between krill fishery and fish community which associated with krill swarms. Data from krill fishery can provide a useful scientific platform to produce biological information of species associated with krill population.