The invention provides a 650V aluminum electrolytic capacitor working electrolyte, and an aluminum electrolytic capacitor made by using the electrolyte. The aluminum electrolytic capacitor working electrolyte is composed of solutes, solvents and an additive, wherein the main solute is fatty acid whose main carbon chain has 32 or 34 carbon atoms and which has a side branch chain or ammonium salt thereof; the auxiliary solute is C8 to C16 carboxylic acid; the main solvent is selected from ethylene glycol, n-butanol, diethylene glycol, n-octanol, gamma-butyrolactone, and butyl acetate; and the auxiliary solvent is selected from benzyl alcohol, 1-hydroxy-2-methoxyethane, diethylene glycol monomethylether, ethylene glycol monobutyl ether, propylene glycol or diethylene glycol. The aluminum electrolytic capacitor has advantages of high voltage resistance, large ripple current, long service life and the like, and fills blanks of the aluminum electrolytic capacitor that the national rated voltage reaches 650V.