A plurality of battery modules (42) is separately mounted at the front and back of a middle cross member (20), and a main switch (29) and a junction board (28) are respectively arranged on the front and back side of the middle cross member (20) in the battery pack for an electric car. Thereby, the maximum car space can be secured. The bent portion of a second high-tension cable (65) that is bent in a U-shape and passes through below the middle cross member (20) is held by a cable holder (69) and fixed to a fixed portion, and thus the second high-tension cable (65) can be easily wired. Only a bus bar (74) that is interposed as the intermediate portion of a first high-tension cable (68) is bent in a U-shape and is set to pass through below the middle cross member (20), and thus it is possible not only to facilitate the wiring of the first high-tension cable (68) but also to minimize the length of the bus bar (74) and improve the reliability with respect to vibration.