This paper reports the results of avalanche prevention by slope benching including restoration of on-slope shrub and tree vegetation that enhances avalanche prevention effect. The slope benching was conducted in 1993 to prevent snow slide on a mountain slope along a road under construction in northwestern Hokkaido Prefecture, Japan. The annual snow depth reaches 3 m around there. The slope is 330 m long. The elevation difference between the roadside and the mountain ridge is about 200 m. The slope area is 1.6 ha. To prevent soil erosion, a water channel was dug on each bench. Neither steel nor concrete was used in the benching work. Before the benching, most of the slope surface was covered with chishima-zasa (Sasa kurilensis: a short, thin bamboo) and scattered trees. Avalanche debris including roots from uprooted trees was observed at the end of down slope almost every year. The debris accumulation is caused when the smooth stems and leaves of the hardy wintering chishima-zasa fall and cause the snow accumulated on the slope to glide easily. After the benching, which structurally mitigated snow glide, the bench surface became covered with shrubs and trees over time. Sakhalin spruce were planted on a part of the slope for growth comparison with the natural replacement vegetation. Four observation plots were established on the slope in 1998 to measure plant growth rates. Each plot was 3 m x 1 m. The results of the benching work follow: (1) No avalanche was observed after the benching; (2) Shrubs and trees recovered, with particularly predominant growth of Japanese mountain birch; (3) Eight years after the benching, the mean height of Japanese mountain birches scattered in the four observation plots on the slope was between 5 cm and 270 cm. Several Japanese mountain alder grew taller than 4 m; and (4) Naturally regenerated trees grew better than the planted plants. The benches are now completely covered with natural shrubs and trees. The benched slope can no longer be distinguished from its surroundings. We achieved avalanche prevention using an eco-friendly measure. This paper reports effects of experimental slope benching as a countermeasure to avalanche, and tree growth on the slope that have been observed from 1993 to 2001.