ABSTRACT
<p><b>OBJECTIVE</b>To ascertain the relationship between glycyrrhizinic acid content and the underground part growth character of Glycyrrhiza uralensis and provide the theoretical evidence for wild resources protection and artificial cultivation method of G. uralensis.</p><p><b>METHOD</b>Through the analytical investigation on the underground part of G. uralensis and analysis of glycyrrhizinic acid content in different organs, parts, ages, and diameter medicinal materials, the systematic study on the relationship between glycyrrhizinic acid content and the underground part growth character of glycyrrhiza uralensis was carried out.</p><p><b>RESULT</b>The underground part of a G. uralensis seedling consisted of seed root, random root, horizontal underground stem, vertical underground stem and assimilating root. The glycyrrhizinic acid content in horizontal underground stem with the age below two years old or in random root with the diameter below 0.5 cm was low. The difference of glycyrrhizinic acid content among horizontal underground stem, random root and vertical underground stem was obvious, but the difference between horizontal underground stem and random root was not obvious.</p><p><b>CONCLUSION</b>The horizontal underground stem was of G. uralnesis acts as a link that can connect random root, vertical underground and stem assimilating root, so that the whole underground part constructs one huge underground net system. The glycyrrhizinic acid accumulation is a effected by organ type, growth age, root diameter and grow position, and the distribution pattern of random root and vertical underground stem has influence on glycyrrhizinic acid distribution in horizontal underground stem.</p>