The invention relates to a quick junction box for optical cables, comprising a base, a fiber fusion disc mounted on the base through a support and an enclosure packaged on the base and receiving the fiber fusion disc; an optical cable incoming wire and an optical cable outgoing wire run through and are fixed to the base respectively, the base is also fitted with a fiber flange fixture, a plurality of fiber flanges are mounted on the fiber flange fixture, optical cable incoming wire fiber cores are each in fusion connection with one single-end jumper fiber on the fiber fusion disc, the single-end jumper fibers are correspondingly connected to top ends of the fiber flanges respectively, optical cable outgoing wire fiber cores are in corresponding connection with the bottom ends of the fiber flanges, and the enclosure or the base is fitted with a humidity sensing alarm device. The quick junction box is simple in overall structure, stable and reliable, and convenient to maintain, the difficulty in cable laying construction can be greatly reduced, signal transmission reliability can be greatly improved, and working efficiency can be improved.