The invention belongs to the technical field of a conductive binding agent, and particularly relates to a preparation method of a positive electrode composite conductive binding agent for a lithium ion battery. The method comprises the steps of firstly, taking polyvinylidene fluoride as a matrix, and forming a MWCNTs/PVDF composite suspension liquid from a carboxylation carbon nanotube by solutionmixing; secondly, polymerizing a conductive polymer monomer on a surface of the composite suspension liquid; and finally, performing drying and smashing to prepare a composite binding agent material.According to the preparation method of the positive electrode composite conductive binding agent for the lithium ion battery, the carboxylation carbon nanotube and the polyvinylidene fluoride are mixed, the carboxylation of the carbon nanotube accounts for 3-10%, carboxyl can be introduced on the premise that a network structure of the carbon nanotube is not damaged and favorable mechanical property is maintained, and the adhesion performance of the composite conductive binding agent is improved.