This study was carried out in order to survey the soil physico-chemical, morphology and content of saponins of 5 year-old Platycodon grandiflorum radix from different areas in Gyeongnam. Soil physical properties was showed 1.01-1.29 of bulk density of soil and soil hardness was increased with increasing soil depth, especially below the 30 cm, however it was maintained or small increased below the 40 cm. T-N and OM contents of top soil were highest at Geochang as 0.27% and 56.9 g/kg, respectively, compared to other areas. The root length was longer at Kimhea and Geochang as 33.8 and 33.7 cm, respectively, and fresh weight was heavy at Geochang as 208.5 g. The contents of saponin of P. grandiflorum radix was higher in fine root compare to main root. By region, content of saponins of P. grandiflorum radix were higher at Hapcheon than other area. Mg content was highly negatively correlated at p ＜ 0.01 with platycodin D3, deapioplatycodin D, platycodin D, and deapioplatycodin D (-0.499**, -0.433**, -0.421**, -0.511** respectively). These results suggest that no-fertilized Mg effected on the improvement of saponin contents in P. grandiflorum.