The invention, belonging to the technical field of industrial microbiology, discloses an extraction method of a cell wall bound biodemulsifier, comprising the following steps: mixing demulsifying bacteria powder which is used for producing the cell wall bound biodemulsifier and alkali liquor with stirring, and carrying out centrifugation, neutralization, condensation, dialysis demineralizing, and freeze drying to obtain the cell wall bound biodemulsifier. The method has the advantages of simple process and high extraction efficiency, can keep the functional activity of the extract product to a great extent, is beneficial to the detection and purification of the biodemulsifier and further revealing of the demulsification mechanism of the biological demulsifying bacteria, and provides a theory basis for the culture and large scale industrial application of the biological demulsifying bacteria.