We studied the morphology and diversity of retinal ganglion cells in Steller's sculpin Myoxocephalus stelleri. The cells were retrogradely labeled with horseradish peroxidase and examined in retinal wholemounts. A sample of 123 cells were camera lucida-drawn and digitized. A total of 18 structural parameters were estimated for each cell. The cells were classified using 10 clustering algorithms. The optimum solution was determined using silhouette analysis. It contained eight clusters and was based on three variables: dendritic field area, vitread stratification boundary, and stratification range. Kruskal-Wallis analysis of variance (ANOVA)-on-Ranks with post-hoc Mann-Whitney U-tests showed significant pairwise between-cluster differences in two or more of the original variables. The present classification is compared with those proposed for other teleosts. J. Comp. Neurol. 525:1122-1138, 2017. © 2016 Wiley Periodicals, Inc.