The invention provides a preparation method of glyphosate potassium salt solid wet product or relative raw pesticide, which comprises mixing solid glyphosate with some water, to be added and reacted with alkali containing potassium cation, controlling the reaction temperature, cooling, crystallizing and drying to obtain glyphosate potassium salt drug. The invention further provides a preparation method of glyphosate potassium salt raw pesticide, which comprises that solid glyphosate is mixed some water, to be added and reacted with alkali containing potassium cation, the reaction mixture is directly dried to obtain glyphosate potassium salt raw pesticide. The invention further provides a high-content soluble solid glyphosate potassium salt. The inventive glyphosate potassium salt raw pesticide, compared with other glyphosate potassium salts, has better weeding speed and rain resistance in same conditions, while the potassium ions on leaf and in soil can be effectively absorbed by plantto feed potassium fertilizer. And the invention has simple package, storage and transmission of prepared glyphosate potassium salt raw pesticide, to reduce cost.