Two field experiments were conducted to evaluate the effects of ascorbic (AsA), humic (HA) and nicotinic (NA) acid on certain biochemical constituents that influence seed quality of Fenugreek (Trigonella foenum-graecum L.). Results indicated that presoaking or presoaking plus spraying in by AsA, HA and NA increased flavonoids, alkaloids, trigonelline, protein, total carbohydrates and oil percentage in seeds. With all tested metabolic inducers (MI), the enhancing effect was more pronounced at its higher adopted level and when it was applied as a combined presoaking plus a foliar spray treatment. Total alkaloid percentage was highest in response to HA at 3000 mg/l whereas trigonelline percentage recorded highest value in response to AsA at 200 mg/l. On the other hand, total phenols percentage was generally decreased with exogenous application of all MI, and the reduction was more evident at the higher level of either AsA, HA or NA. Based on the obtained results, it could be concluded that metabolism of Fenugreek (Trigonella foenum-graecum L.) could be modulated toward the accumulation of beneficial components by exogenous application of AsA, HA, and NA.