To provide a battery module connection structure having a shorting prevention function, a battery module, and a battery module terminal assembly method.

An inter-module connection part 100 includes a nut 105 engaged with an opening 104 of a bus bar plate 7, an O ring 102 engaged with a groove 108 formed at the top of a hollow part 103 of a bus bar cover 8, and a collar 101 placed at the top of the O ring 102. The collar 101 is fixed with a bolt, but before being fixed in place, a space 107 is formed between the collar 101 and the nut 105 by the O ring 102. Then, when a bolt is screwed into the nut 105, the O ring 102 is pushed under pressure, thereby eliminating the space 107.