An electrical connection box is provided. The electrical connection box includes a case having a bottom plate having a terminal connection portion, a cover having a top plate and assembled by being covered on an upper portion of the case, and a plurality of component mounting portions provided on the top plate of the cover. A component including a terminal is assembled in the component mounting portion from above the cover. The terminal of the component assembled to the component mounting portion is connected to the terminal connection portion of the case. At least one boss for maintaining a distance between the bottom plate of the case and the top plate of the cover is provided on the case or the cover. The boss is disposed in a component mounting area surrounded by an outer periphery of the plurality of component mounting portions in a plan view.