The article reviews the emerging field of mixed-dimensional van der Waals (vdW) heterostructures, which integrate two-dimensional (2D) materials with non-2D materials through van der Waals forces. These heterostructures, including 2D-0D, 2D-1D, and 2D-3D combinations, offer unique properties and potential applications in solid-state devices. The review highlights the challenges and opportunities in fabricating and characterizing these heterostructures, emphasizing their superior performance in logic devices, photodetectors, photovoltaics, and light-emitting diodes. Key advancements, such as the integration of graphene with organic semiconductors and the use of mixed-dimensional heterostructures in high-speed photodetectors and photovoltaic cells, are discussed. The article also explores the potential of mixed-dimensional heterostructures in light-emitting devices, noting the need for surface passivation and innovative device designs to maximize radiative recombination. Overall, the review underscores the significant growth potential of mixed-dimensional vdW heterostructures in both fundamental research and applied technologies.The article reviews the emerging field of mixed-dimensional van der Waals (vdW) heterostructures, which integrate two-dimensional (2D) materials with non-2D materials through van der Waals forces. These heterostructures, including 2D-0D, 2D-1D, and 2D-3D combinations, offer unique properties and potential applications in solid-state devices. The review highlights the challenges and opportunities in fabricating and characterizing these heterostructures, emphasizing their superior performance in logic devices, photodetectors, photovoltaics, and light-emitting diodes. Key advancements, such as the integration of graphene with organic semiconductors and the use of mixed-dimensional heterostructures in high-speed photodetectors and photovoltaic cells, are discussed. The article also explores the potential of mixed-dimensional heterostructures in light-emitting devices, noting the need for surface passivation and innovative device designs to maximize radiative recombination. Overall, the review underscores the significant growth potential of mixed-dimensional vdW heterostructures in both fundamental research and applied technologies.