Provided is an electrical connection box in which a greater number of fuses can be inserted while suppressing an increase in size. An electrical connection box for a vehicle includes: an insertion housing that has a rectangular open port on one side and in which a plurality of rectangular insertion holes into which fuses are to be respectively inserted are provided facing the open port; a first insertion hole row in which a plurality of the insertion holes are provided side by side in a lengthwise direction of the open port, with long sides of the insertion holes adjacent to each other; and a second insertion hole row in which a plurality of the insertion holes are provided side by side in the lengthwise direction of the open port, with short sides of the insertion holes adjacent to each other.