The dimethyl silicone oil is dissolved in a suitable solvent to make a silicone solution type defoamer. Organic silicone defoamers formulated with organic solvents such as polychloroethane, toluene and xylene. It can be used for defoaming in oil-soluble media; and organic silicone defoamers formulated with easily soluble water-soluble organic solvents such as hexanediol and glycerin. Can be used for defoaming of aqueous solution. The solution-type silicone defoamer preparation process is very simple. It is easy to use. Silicone oil is dispersed in the foaming liquid by means of an organic solvent to play a defoaming role. At the same time, some solvents also play a role in defoaming during the diffusion process. However, this method has not been used in large quantities, mainly because a large amount of use will increase the cost of the defoamer and may cause environmental pollution.