Please use the following format when citing the article: Kolosej R., Jonuškienė I., Venskutonis P. R., Kazernavičiūtė R., Brazienė Z., Jakienė E., Kvederavičiūtė K., Kanopka A., Vilys L., Mickevičius V. 2017. The influence of β-alanine derivative products on spring oilseed rape yield and oil quality. Field experiments showed that 125 mg l -1 NPNDT solution had the greatest effect on plant growth. In this treatment, the number of secondary branches increased by 54%, the rapeseed yield by 23% compared with the control treatment. The highest seed number per silique (24.5 seeds, or 7.5% higher than in the control) was determined in the treatment where oilseed rape seedlings had been sprayed with 75 mg l -1 NPNDT solution. The highest oil and protein contents in rapeseed were determined in the 75 mg l -1 NPNDT treatment. Compared with the control, a statistically significant increase in rapeseed oil amounted to 137.9 kg ha -1 or 17% and protein content to 6.2 g 100 g -1 or 31%. The increase in rapeseed yield was statistically significant (P < 0.05) in all treatments. The increase of oil content was positively correlated with the seed yield increase (P < 0.05) when oilseed rape was sprayed with the 50 mg l -1 concentration of NPNDT solution. The NPNDT had a positive effect on oil quality. It increased protein and flavonoid contents, reduced ash content in rapeseed and increased DPPH radical scavenging in rapeseed extract.