An electrical junction box includes a case that includes a bottom plate portion and a case-side peripheral wall portion, the case having an opening that opens to a lateral side, and a cover that closes the opening of the case and includes a lid plate portion and a cover-side peripheral wall portion covering a perimeter of the case-side peripheral wall portion. A protruding length of a second upper plate portion of the cover-side peripheral wall portion that is located on the upper side in a state in which the electrical junction box is used is set at such a length that the second upper plate portion protrudes slightly outward beyond an outer surface of the bottom plate portion.