To provide an eaves top parting structure capable of preventing a gap from being produced between an eaves top parting member and an external facing member even if the eaves top parting member is engaged with the end of an eaves top member precut in a plant; and a method of constructing the eaves top parting structure.

The eaves top parting member 15 comprises an eaves top parting member body 16 and an adjusting member 17. The eaves top parting member body 16 is engaged with the end of the eaves top member 10. The adjusting member 17 is disposed in the gap between the eaves top parting body 16 and the external facing member 2 and bought into contact with the external facing member 2 in the state of being partially overlapped with the eaves top parting member body 10. Consequently, even if the eaves top parting member 15 is engaged with the end of the eaves top member 10 precut in a plant, a gap is not produced between the eaves top parting member 15 and the external facing member.