High-efficiency nontoxic insecticide and preparation method thereof

The invention relates to a high-efficiency nontoxic insecticide and a preparation method thereof. The high-efficiency nontoxic insecticide is prepared from the following components in parts by weight: 100 parts of water, 2-30 parts of euphorbia extract, 5-50 parts of pepper extract and 15-40 parts of tobacco stem extract, wherein the euphorbia extract is extracted from daphne euphorbia plants, the pepper extract is extracted from pepper fruits, and the tobacco stem extract is extracted from tobacco leaves. The insecticide is nontoxic and harmless to human beings and livestock without polluting environment and crops or leaving toxicity. The invention has the action of preventing plant diseases and insect pests of crops, fruit trees and vegetables and preventing and curing various plant diseases and insect pests of aphids, cabbage caterpillars, and the like and has low cost, good prevention effect, long insecticide potency durability, less insecticide times and labor saving, thereby stimulating the healthy growth and the prematurity of crops, improving the product quality of crops and increasing the yield.