The invention belongs to the field of new energy, and especially relates to a preparation method for a manganous silicate / carbon water system button-type supercapacitor. The method is characterized inthat a positive electrode material is prepared by 80-85% of a manganese silicate / carbon composite material, 10% of a conductive agent and 5-10% of binder by mass; a positive electrode sheet, a negative electrode sheet and a membrane are pre-soaked in an electrolyte to make them fully wet; a negative electrode shell, a current collector, the negative electrode sheet, the membrane, the positive electrode sheet, a current collector and a positive electrode shell are sequentially assembled from the bottom to the top; the electrolyte is dipped into the negative electrode shell before the closing of the positive electrode shell, and all contents are enabled to be soaked in the electrolyte; the positive electrode shell is closed, is tightly pressed in a sealed manner and is placed quietly, and the manganous silicate / carbon water system button-type supercapacitor is obtained. The prepared manganous silicate / carbon water system button-type supercapacitor is simple in structure, is compact in size, is good in energy storage, is long in service life, is low in cost, is long in storage time, and can be widely used for new energy automobiles and consumer electronics.