Abstract: A fluid withdrawing, expelling and filtering apparatus includes a fluid container including a first chamber, a second chamber, and, a first through hole and a second through hole respectively disposed in communication between the first chamber and the second chamber, a filter device movable between a first position and a second position to open or close the second through hole of the fluid container and including a filter element mating with the first through hole, and a fluid withdrawing and expelling operator operable to withdraw and expel a fluid through the first chamber of the fluid container.