In this study, the structural, biological and technical aspects of rainbow trout (Oncorhynchus mykiss) hatcheries in Malatya Province were investigated. The raw data of the survey work to be done face to face with the authorized persons and employees in the company has been obtained in real time. According to the results, it was determined that the rainbow trout hatcheries actively working in Malatya Province are five small-sized (˂2 million fry fish/year), three medium-sized (2-10 million fry fish/year) and two large-sized (>10 million fry fish/year) capacity. The management structure of these companies was 50% company-partnership, 40% person-family business and 10% cooperative. The proportions in the total capacity of the small-scale, medium-scale and large-scale enterprises was found as 4.18%, 44.15% and 51.68%, respectively. Total projected capacity of these hatcheries was determined as 52 994 292 number fry fish/year. However, the amount of fry rainbow trout production belong to these enterprises was found as 21 514 292 number fry fish/year. Average capacity usage rate of the hatcheries in Malatya Province was determined as 40.6%. This rate for the small, medium and large-scale hatcheries was calculated as 59.85%, 42.22% and 38.34%, respectively (p˂0.05). The large (76.7%) and medium (70.2) scale enterprises have significantly higher (p˂0.05) production efficiency than the small capacity enterprises (63.61%). Mean production efficiency value for this enterprises was found as 74.44%. Differences in the structural, biological and technical characteristics of existing enterprises directly affect their capacity usage rate and production efficiency