To provide a collapsible support base in which a support recessed part suitable for housing and supporting, for example, a bonfire base or the like is formed in the shape of an inverted pyramid, which can be easily folded and superposed in a flat state when it is not used, and is conveniently housed and excellent in its portability and mass production and simply manufactured.

A prescribed number of support plates 2 having flat legs 3 are provided by forming the leg 3 protruding in the direction of the plane of the support plate 2 on the lower part of the support plate 2 which forms one of respective pyramidal planes. Side edge parts of the adjacent support plates 2 are pivotally connected so as to be rotatable inward a support recessed part 1 so that the support recessed part 1 is formed with the support plates 2. When the adjacent support plates 2 are rotated to form the support recessed part 1 in the shape of an inverted pyramidal recess using the support plates 2 as pyramidal planes, the legs 3 of the support plates 2 are grounded and supported so that the form of the support recessed part 1 is maintained. The adjacent support plates 2 can be folded and superposed in a flat shape through pivot parts 4 on which the adjacent support plates 2 are pivoted.