Most soybean sprouts grown in factories are sold on the market. When the soybean sprouts grow up to lateral root initiation, the rate and absolute amount of asparagine in the roots of all sprouts are comparatively low. To extract the greatest amount of asparagine from soy-sprouts, it is advantageous to grow sprouts more than 16 days. When sprouts were grown with ozonic water, it was possible to grow sprouts more than 16 days without any rotting problems. The content of asparagine in the sprouts were proportionally increased up to 16 days. When sprouts were grown in 0.2% of urea, the content of asparagine in sprouts were significantly increased. Soybean sprouts grown at room temperature showed the highest yield rate and asparagine content, at the same time.