To provide a habitable room structure of ships which can reduce the area of habitation space.

The ship includes a plurality of individual cabins 3A to 3D in a habitation space. The habitation space includes a corridor 2 and a habitation unit U which has at least four individual cabins 3A to 3D which are arranged two by two on the left and right sides of the corridor 2 along the corridor 2. The habitation space consists of a plurality of habitation units U which are arranged in predetermined places. The corridor 2 has sharing lighting windows 22 opening outward. The four individual cabins 3A to 3D have an individual cabin lighting window 32 opening toward the corridor 2, respectively. The four individual cabins 3A to 3D have beds 33U and 33L, respectively. In the two adjoining individual cabins 3A and 3B; and 3C and 3D the beds are arranged to overlap each other in the vertical direction.