• 3D graphene overcomes the limitations of 2D graphene by providing enhanced light absorption through its porous structure and optical microcavity effects.
• The unique properties of 3D graphene, including large specific surface area and high chemical stability, make it a promising material for high-performance photodetectors.
• This review systematically analyzes synthesis techniques and heterojunction strategies for 3D graphene-based photodetectors.
• The paper identifies current challenges and proposes feasible development paths to promote industrial application of 3D graphene photodetectors.