PROBLEM TO BE SOLVED: To provide a method for producing a three-dimensional network structure dispensing with the post-finishing treatment, increasing the aligning degree and enabling the production of an article having non-regular shape and improved durability and provide an apparatus for the production method. SOLUTION: This three-dimensional network structure 1 is a plate structure produced by using a thermoplastic resin as the raw material or a main raw material and containing plural filaments disorderly entangled with each other in spiral form and bonded by partial thermal bonding. The density of either one of the three or four surfaces of the outer circumference of the three-dimensional network structure is preferably low relative to the density of the part excluding the above surface. The raw material or the main raw material of the thermoplastic resin is flakes or chips of PET bottle produced by crushing the PET bottle as it is and melting in the form of flakes. The method meets the trend of the promotion of recycling and reduces the disposal cost of waste materials. The three-dimensional network structure 1 can be used mainly as a shock absorber, cushioning material, sound-absorbing building material, etc.
