Abstract: The oil amounts of raw and roasted mustard seeds were reported between 12.05 (control) and 16.30% (oven). Total phenolic and flavonoid amounts of untreated (control) and roasted mustard seeds were recorded to be between 473.90 (control) and 569.96 mgGAE/100 g (oven) to 345.48 (control) and 479.76 mg/100 g (microwave), respectively. Antioxidant capacity results of untreated and roasted mustard seeds were determined to be between 6.71 (oven) and 6.97 mmol/kg (control). Total phenolic and flavonoid amounts of oven-roasted seeds were higher than those of control and microwave-roasted seeds. L* values of mustard seeds varied between 35.04 and 65.52. Heat treatment caused a decrease in L* values. The lowest L* value was observed in the sample dried in conventional oven. The quantitative values of gallic and 3,4-dihydroxybenzoic acids of mustard seeds were recorded to be between 8.47 (control) and 117.31 mg/100 g (microwave) to 2.16 (control) and 11.79 mg/100 g (microwave), respectively. Erucic acid values of the oils extracted from raw and roasted mustard seeds were reported between 41.38 (control) and 42.81% (microwave). Oleic and linoleic acid amounts of mustard oils differed between 26.06 (microwave) and 26.90% (control) and between 13.08 (oven) and 13.98% (control), respectively. The oven roasting system had the most effect on the element and protein contents of the seeds, followed by the microwave in decreasing order. As with the bioactive components of the seeds, the amounts of phenolic constituents of roasted mustard seeds increased significantly compared to the control. Graphical abstract: (Figure presented.)