Soybean has been considered as an important source of food protein in many countries. This experiment was attempted to determine the effect of mineral nutrition on growth and amino acid composition of soybean by using the methods developed for other plants. The results showed that S was more effective than P on the growth of soybean when the amount of cation was not changed. Among cations investigated K was more effective than Mg and Ca on its growth. However, higher amounts of Ca resulted in toxic effect. In general, the content of amino acid hydrolyzed by HCl decreased in NS and NP as well as KCa and KMg groups. Amino acids, i.e., proline, cystine, aspartic acid, lysine and histidine were not detected in NS and NP in addition to KCa and KMg groups eventhough control group showed considerable amount of these amino acids.