The invention relates to an electrolytic capacitor having a flame retardant electrolyte and a high safety even if the electrolyte leaks out to outside, and more particularly to an electrolytic capacitor comprising a positive electrode provided with an insulating oxide layer formed through anodic oxidation, a negative electrode, a separator and an electrolyte containing a solute in an organic solvent, characterized in that the electrolyte contains not less than 3% by mass of a phosphazene derivative and/or an isomer of a phosphazene derivative.