A filter device of the present invention includes a hydrophilic filter located in a vertical space in a filter housing to filter off solid impurities in an introduced liquid, at least one hydrophobic filter located corresponding to at least one gas discharge hole provided in the filter housing, the hydrophobic filter allowing gas in the introduced liquid to be discharged to the outside before and/or after the liquid passes through the hydrophilic filter, and a blocking member for preventing gas in the liquid passing through the hydrophilic filter from flowing into the outlet tube, the blocking member being installed in the filter housing to block the outlet tube, the blocking member having a longitudinal passage formed in a center portion thereof so that the liquid is introduced into the outlet tube through the passage and discharged therefrom. According to the present invention, there are advantages in that the filter device can effectively remove air and impurities such as solid particles contained in a liquid such as a medicine, prevent the air in the medicine from flowing into an extension tube connected to the filter device, and ensure a maximum surface area of a hydrophilic filter for filtering off solid particles such as glass fragments so that a flow rate of a medicine passing through the filter device does not decrease.
