An electrical junction box including a box main body and a wiring block. The box main body includes a cassette block. The wiring block includes a first bus bar, a second bus bar, and a fuse. Each bus bar includes an electric parts connecting part and the power source connecting part. The electric parts connecting part is connected to electric parts attached to the cassette block. The power source connecting part includes a fuse connecting piece and a connecting piece. A terminal fitting connected to a power source is connected to the connecting piece. The fuse connects the fuse connecting pieces of the bus bars.