Brown (laulau) and white mustard are of great interest as oil crops. They differ from each other by architectonics of structure and quality traits but have the same economic value, being an important source of vegetable oil for food and technical industries. Mustard is adapted to cultivation in regions with relatively low humidity and sufficient precipitation, with moderate temperatures during the growing season. Bioclimatic conditions of the forest-steppe and steppe zones of Western Siberia, including the Omsk region, are suitable for the cultivation of spring mustard. The purpose of the work is to determine the potential yield of brown and white mustard depending on weather conditions in Western Siberia, to evaluate promising mustard samples of the breeding of V.S. Pustovoit All-Russian Research Institute of Oil Crops (VNIIMK) on the main economically important traits. Varieties and promising samples of brown and white mustard were tested on the experimental fields of the Siberian experimental station (branch of VNIIMK) in 2019-2021. The average yield of brown mustard variety Valenta during the years of research was 2.46 t/ha. The variety is adapted to Siberian conditions, drought-tolerant, the maximum seed yield of 2.84 t/ha was obtained in the critical conditions of water availability of 2021. During the research, a highly productive sample № 21 of brown mustard of the breeding of VNIIMK was selected by the main economically important traits. The promising white mustard samples 698 and 702 and the variety Bella with the potential yield of 1.34-1.42 t/ha and the oil content of seeds 28.5-29.5% positively exceeded the standard variety Raduga by the main indicators.