To provide an electrical junction box in which an electrical junction box body includes one casing and the other casing, the other casing is prevented from being lifted from the one casing, and a bracket can be attached to a peripheral wall portion of the other casing stably and strongly. One casing is fitted in the other casing. A peripheral wall portion of the other casing is provided on an outer peripheral surface with engagement lock portions. A bottom wall section of the one casing is exposed from an opening defined by the peripheral wall portion. A fitting projection portion is provided on the bottom wall section near the engagement lock portions. The bracket is mated with the engagement lock portions. The fitting projection portion is mated with a fitting recess provided in the bracket to attach the bracket to the other casing.