Based on the three-dimensional graphene material, a broadband stretchable terahertz absorbing material was developed by combining 3D graphene materials with Polydimethylsiloxane(PDMS) film. The designed structure allows the three-dimensional graphene to achieve substantial stretching under the protection of the polydimethylsiloxane layers. The experimental results show that the composite structural material has a maximum absorption rate of 90% in the test range of 0.2-1.1 THz, and the terahertz wave absorption rate of the composite structure remains substantially unchanged under a tensile force of 20%. In addition, the structure and properties of the material sample can be restored to the original state when the external force is removed. Stretchable terahertz absorbing materials have the advantages of high bandwidth, high absorption rate, simple processing and large-area preparation, which has a great potential applications in field such as terahertz absorbers.