Provided are an insulin-lipid complex, a preparation method therefor, and a preparation thereof. The insulin-lipid complex is prepared by compounding insulin and a lipid material in an organic solvent system containing a low-melting point acid, and drying. The weight ratio of insulin to the lipid material is 1:3-1:20. A solution of the insulin-lipid complex in an oil and in vesicles containing insulin are further provided.