There are presented the results of studying the influence of mineral fertilizers on productivity of spring rapeseed varieties depending the seed sowing rates. We studied released rapeseed varieties Kupol and Granit. The experiment was conducted in a breeding crop rotation of cole crops on fields of the Siberian experimental station – a branch of VS. Pustovoit All-Russian Research Institute of Oil Crops in the southern forest-steppe of the Wester-Siberial region in 2020–2021. The following methods were used: field observations (phenological accounts and estimation of lodging by points), laboratory (determination of yield, 1000 seed weight, plant yield structure) and biochemical analyses (determination of oil and glucosinolate contents in seeds). We studied relations in three-factor experiment: factor А – varieties; factor В – seed sowing rates; factor С – mineral fertilizers. Application of mineral fertilizers increased the average meanings of seed yield: for the variety Kupol – from 24.6 (control) to 30.9 quintal/hа (N30P60). Yield increase on average for three years was 6.3 quintal/hа, and the maximal yield of 33.3 and 33.1 quintal/hа was obtained in 2021 under application of N30P60 and seed sowing rate of 1.25 and 1.75 mln viable seeds/ha. The variety Granit responded well on the mineral fertilizers. Average for two seed yield increased from 26.6 to 32.5–32.6 quintal/hа under fertilization and seed sowing rate of 1.75 and 1.25 mln viable seeds/ha.