A bus bar module comprising: a case configured to be assembled to a battery assembly body including a plurality of electric cells; and a bus bar configured to be supported in the case and connected to electrodes of the electric cells of the battery assembly body, wherein the case includes a first divided case comprising a female lock portion and a second divided case comprising a male lock portion, said cases (22, 23) being divided in an arrangement direction of the electric cells and coupled at a coupling portion, the coupling portion comprising a first coupling portion including the female lock portion of the first divided case and the male lock portion of the second divided case, wherein the female lock portion includes a locking frame provided with a gap spaced apart from an end surface of the first divided case, wherein the male lock portion includes a pair of elastic arms extending from an end surface of the second divided case and having at least two bending points, a support plate portion spanning end portions of the elastic arms between each other, a locking plate portion formed on the support plate portion and inserted into the gap of the female lock portion, and a lock claw provided on the locking plate portion and locking the locking frame by inserting the locking plate portion into the gap, and wherein the support plate portion of the male lock portion has slits at a side of the elastic arms; wherein the first coupling portion is provided between bus bar housing portions in which the bus bar is housed, wherein the coupling portion further includes a second coupling portion in which a male lock portion is engaged with a female lock portion between electric wire routing groove portions (31A, 31B) in which an electric wire is routed, and wherein the second coupling portion is provided at a position adjacent to the first coupling portion in a width direction of the case; wherein the second coupling portion comprise an engagement hole portion formed of a hole that is longer than the engagement protrusion. a case configured to be assembled to a battery assembly body including a plurality of electric cells; and a bus bar configured to be supported in the case and connected to electrodes of the electric cells of the battery assembly body, wherein the case includes a first divided case comprising a female lock portion and a second divided case comprising a male lock portion, said cases (22, 23) being divided in an arrangement direction of the electric cells and coupled at a coupling portion, the coupling portion comprising a first coupling portion including the female lock portion of the first divided case and the male lock portion of the second divided case, wherein the female lock portion includes a locking frame provided with a gap spaced apart from an end surface of the first divided case, wherein the male lock portion includes a pair of elastic arms extending from an end surface of the second divided case and having at least two bending points, a support plate portion spanning end portions of the elastic arms between each other, a locking plate portion formed on the support plate portion and inserted into the gap of the female lock portion, and a lock claw provided on the locking plate portion and locking the locking frame by inserting the locking plate portion into the gap, and wherein the support plate portion of the male lock portion has slits at a side of the elastic arms; wherein the first coupling portion is provided between bus bar housing portions in which the bus bar is housed, wherein the coupling portion further includes a second coupling portion in which a male lock portion is engaged with a female lock portion between electric wire routing groove portions (31A, 31B) in which an electric wire is routed, and wherein the second coupling portion is provided at a position adjacent to the first coupling portion in a width direction of the case; wherein the second coupling portion comprise an engagement hole portion formed of a hole that is longer than the engagement protrusion.