AbstractBACKGROUNDMetal nanoparticles are widely used in agricultural production. As a new type of molybdenum fertilizer, MoO3NPs have the properties of nanomaterials and the characteristics of molybdenum nutrition. Previous studies have focused on their role in promoting crop growth. However, it is unknown whether excessive MoO3NPs will affect crop quality and nutritional value. In this study, the effects of different concentrations of MoO3NPs (0, 0.15, 0.5, 1.0, 5.0, 10, 50, 100 mg kg−1) on the growth and quality of soybean were investigated by pot experiments to analyze the plant effects caused by MoO3NPs.RESULTSThe results showed that the effects of MoO3NPs treatment on plant biomass and nodule number were promoted at low concentrations (0.15–5 mg kg−1) and inhibited at high concentrations (10–100 mg kg−1). According to the logistic distribution model, it was predicted that MoO3NPs would have the strongest toxic effect on soybean flowering stage. The contents of MoO3NPs which reduced the yield of soybean by 10% and 20% were 12.38 and 30.81 mg kg−1. NP0.15 could significantly improve the total amount of amino acids in grains, while NP100 reduced the total amount of amino acids in grains, both of them significantly increasing the contents of linolenic acid and linoleic acid in soybean seeds.CONCLUSIONA change of MoO3NPs concentration had no negative effect on the nutritional value of soybean grains. The research could lead to a better understanding of the potential impact of nutritional changes caused by MoO3NPs on human health. © 2024 Society of Chemical Industry.