SummaryIn this study, the effect of roasting, boiling and germination processes on bioactive compounds, antioxidant activity, fatty acid and phenolic profiles and biogenic elements of quinoa seed and oils was assigned. The moisture amounts of boiled and germinated quinoa seeds were recorded to be significantly higher than the control. Also, the oil yield of quinoa seeds decreased compared with the control by roasting, boiling and germinating. The total phenolic and flavonoid quantities of quinoa seeds were assigned to be between 137.70 (germinated) and 315.00 (boiled) to 156.62 (boiled) and 402.38 mg/100 g (control), respectively. Antioxidant capacities of processed quinoa seeds were reported to be between 11.91 (germinated) and 14.43 mmol kg−1 (roasted). The highest total flavonoid and antioxidant capacities were recorded in the control group and roasted quinoa seeds. The highest decrease in total phenol amount of quinoa seeds was detected in germinated quinoa. Gallic acid and catechin values of quinoa seeds varied to be between 29.17 (boiled) and 38.00 mg/100 g (control) to 2.72 (germinated) and 137.26 mg/100 g (control), respectively. The rutin, ferulic acid and p‐coumaric acid contents of the processed (roasted, boiled and germinated) quinoa seeds gradually increased compared with the control. The highest palmitic, oleic, behenic and arachidonic acids were recorded in germinated quinoa oil, followed by the fatty acids of boiled, raw (control) and roasted quinoa seed oils in descending order. P and K amounts of quinoa were established to be between 2203.44 (roasted) and 3314.59 (control) to 4350.60 (boiled) and 6266.85 mg kg−1 (control), respectively.