The utility model provides a novel outdoor seal capacitor box, include box body and box door just the box body with the box door rotates to be connected, the inboard middle part of box door is provided with the mount, it is cotton that the inboard avris of box door is provided with waterproof bubble. The utility model discloses a totally closed design and to set up the waterproof bubble of high leakproofness in box door inboard cotton can be prevented dust, waterproof. Whole condenser block protection level can reach IP67. The utility model discloses the locking screw on the box door is opened with the general utility wrench to installation or when changing the condenser, the box door 90 of unscrewing, and the condenser of installing on the mount can come out along with the box door is rotatory, can install or change the condenser outside, and it is comparatively convenient to operate.