The hard pan of paddy field considerablely influences nutrient absorption and rice productivity. This study was performed to establish the standards of fertilization and soil management through analizing soil environmental properties of Jeonbug series. The hard pan of Jeonbug series(fine silty, mixed, nonacid, mesic family of Fluvaquentic Endoaquepts) is formed thick below surface soil. The hard pan was located on 15 cm below the surface soil in paddy soil of Jeonbug series. The depth of surface soil, hardness and thickness of hard pan were 12.6 cm, 14.7 kgcm-2, 22.3 cm in paddy soil of Jeonbug series, respectively. The soil temperature difference between the hard pan and the surface soil was -2.0°C in spring, -2.5 °C in summer, and -1.0°C in autumn. The changes in each soil layer showed that surface soil had been reduction state since panicle formation stage, but hard pan had been oxidation state till the late heading stage. When the hardness of hard pan was high, the thickness of surface soil was low, and the thickness of hard pan was high. In soil physical characteristics of hard pan, the bulk density and solid phase were high in hard pan, but the porosity and air phase were low in hard pan compared to surface soil. The contents of OM, T-N, phosphate were low in hard pan, but pH, SiO2, Ca, Mg were high in hard pan compared to surface soil. K and CEC practically showed the same contents in both soil layers. The amounts of inorganic nitrogen were less in hard pan than in surface soil, and the contents of soluble Fe and Mn were higher in hard pan than in surface soil. The hardness, bulk density and solid phase ratio of hard pan were lowered by the deep plowing in the depth of 18cm, while the porosity and air phase were increased. The subsoil breaking was more effective than the deep plowing. The contents of OM, SiO2, exchangeable K, Ca, Mg, CEC were increased, by soil diagnosis and deep plowing. Also the effect of subsoil breaking showed the same tendancy with deep plowing. When the depth of surface soil was deeper, the brown spot of rice was lowered.