Abstract: In order to enrich the diversity of quinoa products and develop instant quinoa products,extrusion technology was used to process quinoa flour. The optimum extrusion parameters were determined by response surface method,and the nutritional components,antioxidant activities and starch digestibility of extruded quinoa flour were evaluated. In addition,the effects of extrusion processing on the quality of quinoa flour were also studied. Results indicated that,the optimal parameters were as follows:Moisture content 16.61%,die diameter 4.00 mm,extrusion temperature 140.00℃ and screw speed 160.00 r/min,then the comprehensive score was 88.17. Under the process,protein content was 12.44 g/100 g DW,including 17 kinds of amino acids. Linoleic acid and linolenic acid accounted for 55.38% and 8.07% of total fat(6.32 g/100 g DW),respectively. Besides,the contents of mineral Calcium,Iron and Zinc were high. Extruded quinoa flour contained 2.45 mg GAE/g DW total phenol and 0.29 mg CE/g DW total flavonoids,which also had the DPPH free radical scavenging power of 2.80 μmol TE/g DW,ABTS⁺ free radical scavenging power of 3.34 μmol TE/g DW and Fe³⁺ reducing power of 8.45 μmol TE/g DW. Meanwhile,the starch digestibility was good and in vitro glycemic index was 84.69. After extrusion,quinoa flour exhibited different degrees of loss in some nutritional components. The contents of total phenolic and total flavonoid were decreased,and the antioxidant activities were decreased. However the in vitro digestibility of starch was significantly improved and the product tasted better.