The invention provides an electric dust collector capable of preventing air leakage on tube unit. The electric dust collector has: a whirlwind dust collecting device; a tube unit (1) which guide air from the opening on the whirlwind dust collecting device used as an air outlet to a dust collector main body with a built-in electric blower; a washer component (4) which is used for keeping the air-tightness between the tube unit (1) and the opening part of the whirlwind dust collecting device; and fixing components (5, 6) used for fixing the washer component (4) on the tube unit (1).