To investigate the functional properties of the traditional condiment Xianju wheat paste, antioxidant components were extracted using a high-speed homogenization method, and the extraction conditions were optimized. Antioxidant capacities of Xianju wheat paste from different workshops and with different storage times were evaluated. The optimal extraction parameters were as follows: material-to-liquid ratio of 1:35, ethanol concentration of 60%, extraction time of 6 min, and rotational speed of 8800 r/m. The antioxidant capacities of Xianju wheat paste extracts from different workshops, expressed as equivalents to Vc per gram of wheat paste, were as follows: DPPH radical scavenging ability of 3.47~7.3 mg Vc/g, OH radical scavenging ability of 55.32~7.75 mg Vc/g, ABTS+ radical scavenging ability of 24.32~42.85 mg Vc/g, and FRAP value of 5.8~11.3 μmol/L Vc/g. The antioxidant capacity of Xianju wheat paste increased significantly as storage time increased. The research results indicate that Xianju wheat paste possesses strong antioxidant activity and holds great potential for transitioning into a functional condiment and realizing its immense value.