The invention discloses a saline and alkaline land soil conditioner prepared from bamboo vinegar and relates to the technical field of agricultural planting. The soil conditioner is prepared from raw materials in parts by weight as follows: 13-18 parts of the bamboo vinegar, 30-40 parts of corncobs, 15-20 parts of coconut dust, 15-20 parts of hawthorn leaves, 15-20 parts of leaves of illicium anisatum, 10-15 parts of Chinese arborvitae twigs and leaves, 10-15 parts of leaves of toona sinensis, 8-12 parts of Chinese honeylocust spines, 6-10 parts of bean dregs, 5-8 parts of peptone, 5-8 parts of mineral powder, 4-7 parts of distiller's yeast, 3-5 parts of yeast powder, 3-5 parts of tobacco straw ash and 2-4 parts of grape seed meal. The soil conditioner can reduce the pH value of soil, enrich nutritional ingredients of the soil, adjust physical and chemical properties of the soil and loosen the soil structure, besides, the added mineral powder can play a role in effectively killing bacteria and pests of the soil, treatment of the soil is simplified, so that plant growth is facilitated, and the planting workload is reduced.