A better understanding of coho salmon ovarian maturation will inform both aquaculture and conservation efforts. Ovarian maturation is a complex molecular and physiological process resulting in a mature ovum that can be released for spawning and fertilization. The confluence of molecular signals and pathways that must be co-expressed to accomplish full reproductive maturity with high quality oocytes have been previously investigated with with low-resolution proteomics and transcriptomics. This dataset expands proteomics resources for coho salmon by thousands of proteins, allowing for a more in-depth assessment of the range of proteins involved in ovarian maturation and their interactions. We sampled coho salmon at four ovarian developmental stages that encompass the transition from primary to secondary (vitellogenic) growth. Data independent acquisition proteomics was applied to the dataset, resulting in the inference of >5000 proteins in the coho ovarian proteome.