The purpose of this study was to analyze and report the nutritional and physicochemical properties of 13 barnyard millet varieties (Echinochloa spp.) in Korea. Among the varieties, IT153600 exhibited the highest total protein ($14.75{pm}1.7$%), lipid ($6.92{pm}1.1$%), and amino acids contents ($137.10{pm}3.1$ mg/g), and had a high germination rate ($98.9{pm}1.8$%). For fatty acid composition, the highest linoleic acid ($67.6{pm}2.5$%) content was found in K141285. K141286 varieties exhibited the highest amylose content. The highest mineral content was found in IT153604. Based on excellent agricultural properties, K141285 was selected and investigated for its antioxidant effects using DPPH and ABTS. The 80% methanol extract of K141285 showed significantly high total phenolic ($38.45{pm}0.45$) and flavonoid ($28.71{pm}0.27$) contents. These results suggest that all of the selected barnyard millet (E. spp.) varieties can be considered to be new functional crops due to their antioxidative effects and high nutrient contents.