To obtain a three-dimensional woven fabric structural material widely useful as a heat insulating material, a sound insulator, a reinforcing core material, other interior materials, a composite structural material, an elastic structural material such as a curtain, a blind, etc., a tent, an agricultural protecting material and for other various uses and to provide a method for producing the structural material.

A great number of cylindrical bag parts 2 long and parallel with one direction of length and breadth are integrally woven in a continuously plural line state in the other direction of the length and breadth by multilayer weaving of three or more layers. The cylindrical bag part 2 of each line is composed of a woven fabric layer of at least two layers. The cylindrical bag parts are connected in the other direction through knot parts 3 of the woven fabric layers. The cylindrical bag parts 2 of adjoining lines hold in common the woven fabric layer between both the lines and are formed to be continuous at mutually alternate positions. Folding processing is carried out at the central position between the knot parts 3 in the woven fabric layer of each cylindrical bag part 2. The cylindrical bag parts are set so as to retain folds in a hollow solid state or foldably in a flat state.