The changes of chemical and physical properties of surface and subsurface soils were examined on four old landslide sites on which hillside works had been made 24_??_55 years before and on a new landslide scar. Temporal variations of the soil properties on the landslide sites were compared with those outside their circumferences where landslides had not occurred. The soil profiles on the sites had been developed by reforestation after many years. The total carbon and total nitrogen contents on the sites were generally less than those along their circumferences. These contents gradually increased and approached those in the soils outside their circumfer ences with time. Relationships between the water contents of soils at sampling time and at pFs 1.8 and 2.7, the porosities and clay-fraction contents of soil versus the lapsed years after hillside works showed trends similar to those of the total carbon and total nitrogen contents. The measured values of subsurface soils were smaller than those of surface soils, but the changes of physical and chemical properties of these soils on the sites had the same trends as those of surface soils. Accordingly, it was estimated that the physical and chemical soil-properties on the sites gradually changed quantitatively and qualitatively over the long passing years and approached those of the soils outside their circumferences.