The invention relates to a preparation method of an electrode material of a supercapacitor. The method comprises the following steps: preparing metal-organic framework compounds (8 -hydroxyquinoline-Zn and 8-hydroxyquinoline-Mn) in a reflux way and then calcining in a nitrogen gas atmosphere; adding the calcined metal-organic framework compounds (8 -hydroxyquinoline-Zn and 8-hydroxyquinoline-Mn) in a process of in situ polymerization of aniline, and further stirring for reaction; washing, centrifuging and drying; mixing the treated compound materials, acetylene black and PVDF and grinding; and finally coating a titanium mesh with the ground mixture. Compared with the prior art, the synthesis method disclosed by the invention is simple; the prepared composite material containing polyaniline and the metal-organic framework compounds has relatively high specific capacity and good electrochemical properties and therefore has a good application prospect in term of energy storage in further.