An electrical connection assembly and a connection method enable conductors of first and second wires (10A, 10B) to be connected by a simple structure. The electrical connection assembly has first and second wires (10A, 10B) and first and second terminals (20A, 20B) corresponding to the first and second wires (10A, 10B). First and second connecting members (70A, 70B) made of solder are fixed to wire connection surfaces (27a) of the first and second terminals (20A, 20B), and an insulating housing holds the terminals. The first connecting member (70A) includes a bulging portion (72A) bulging from the wire connection surface (27a) of the first terminal (20A) and to be connected electrically to the conductor of the second wire (10B).