Strong earthquakes (>7.0 Ms) critically change pedosphere, how the changed soils disturb tree root growth related to forest restoration is unclear globally. Therefore, a total of 15 plots were established in non-removed and landslide areas of Cupressus funebris and Cryptomeria fortunei plantations near northern section of fault belt of Wenchuan Earthquake (8.0 Ms) occurring in May 12, 2008, China. 112 and 114 small fine roots (≤2.0 mm in diameter) in all the plots were sampled in June and October of 2009. Mean tips length/length, area/ length, volume/length, mean tips length/biomass, specific root area and specific root length in 0.0–0.5, >0.5–1.0 and >1.0–2.0 mm diameters of roots were examined. This study revealed 1) root parameters did not respond to the landslide soils in the June, but did until the October, suggesting after many root tips and tiny roots die in winter, the roots lose sensitivity to a changing soil environment; 2) mean tips length/length and mean tips length/biomass decreased for Cupressus funebris, and increased for Cryptomeria fortunei as well as area/length and volume/length in the landslide soils, implying both species roots have different processes of forest restoration; 3) the smallest sized roots were more sensitive to the landslide soils than the other sized roots, which are better indicators for the forest restoration.