The disclosed terminal assembly for a circuit interrupter comprises three pairs of opposite source and load terminals 10, 20 each pair being carried on both lateral sides by a pair of first and second side plates 30, 40 by having each lateral side 106,206 and a recess 104, 204 on that side engaging an associated groove 300, 302 and a raised portion 306, 308 on the front surface of each side plate respectively and connected to adjacent pairs of the opposite source and load terminals through different pairs of the first and second side plates interconnected back to back. All the terminals and side plates are assembled into a unitary structure between two metallic plates 70,72 by means of bolts 78, 80 and nuts 84. A supporting strut 60 includes two notches 600, 602 fitted onto the lateral surfaces of end portions of each pair of the opposite source and load terminals 10, 20 and is disposed on each of the side plates. The outermost strut is connected to the adjacent metallic plate through a lateral locking member 86 and each pair of the intermediate struts are interconnected back to back and connected to the interconnected first and second plates through an intermediate locking member 96.