The present invention relates to an apparatus for waterproofing a mobile phone case. The apparatus for waterproofing a mobile phone case is characterized by comprising a lower mold unit in which multiple mobile phone cases are installed; an upper mold unit including a space filled with a waterproofing member on a treatment part of each mobile phone case, coming in contact with the mobile phone case, and comprising a receiving unit receiving the waterproofing member and connected with the space; and a pressing block pressing the upper mold unit to allow the waterproofing member received in the receiving unit to be penetrated into the space, to make the waterproofing member be filled in the space and be cured.
