In this study the physiochemical characteristics and antioxidant activity of soybean curd were prepared with saltwort (Salicornia herbacea L.). The moisture and protein of the saltwort soybean curd showed no difference among the samples. Ash and lipid were found to be the highest in the soybean curd to which 20% saltwort was added. The contents of mineral(Fe, K, Mg, Zn) were highest in the soybean curd to which 20% saltwort was added, and Ca content was high in the soybean curd to which 16% and 20% saltwort was added. DPPH (1,1-dipheny1-2-picryl-hydrazyl) radical scavenging activity is a method of measuring the antioxidant power of food; this was high in the soybean curd to which 20% saltwort was added. Adding more saltwort led to higher scavenging activity. From the above results, it could be seen that the soybean curd, which is made by adding saltwort, contributed to enhancing the functionality of antioxidant activation and product quality.