To provide a multi-purpose space structure unfoldable and foldable easily and movable easily.

When the space structure is unfolded, a lower beam member 3 and an upper beam member 5 are linearly unfolded and fixed. A space usable for a specific purpose is formed with wall members 2A, 2B. The figure shows an example in which the space structure is used as a bedroom by laying down a mat on a floor member 4. When the space structure is folded, the hinge sections 3a, 5a of the upper and lower beam members 3, 5 are unlocked, the upper and lower beam members 3, 5 are bent inward horizontally, the floor member 4 is bent upward about a hinge section 4a according to the bending, and finally all of the beam members and the floor member are stored in the space formed by the wall members 2A, 2B abutted on each other as shown in (A). A table 6 is leaped up and stored in the space.