Human beings are “machines” that use endogenously produced biomolecules as “components” in signaling and for the maintenance of the body. These biomolecules consist of proteins, nucleic acids, and carbohydrates, which can either be extracted from biological substrates or synthesized by chemical/biochemical methods. These biomolecules have the ability to recognize/interact with other biomolecules that are overexpressed in disease cells. For targeted theranostics, strategies to chemically incorporate these natural biomolecules with advanced materials to treat human diseases by imaging‐guided drug delivery or photodynamic/photothermal therapy are proposed, with improved biocompatibility. Herein, recent research on construction of quantum dots, nanoparticles, and 2D material platforms decorated with antibodies, peptides, nucleic acid aptamers, carbohydrates, and folic acid for targeted diagnosis and treatment are summarized and discussed. In addition, the various strategies required to construct effective functional materials for targeted cancer therapy are highlighted. The hope is that this review can inspire and guide those that are interested in the field of biomedicine to rationally design and develop new target‐based theranostic materials. Recent research progress on the construction of quantum dots, inorganic nanoparticles, conjugated polymers, and 2D material platforms decorated with antibodies, peptides, nucleic acid aptamers, carbohydrates, and folic acid for targeted diagnosis and treatment are summarized and discussed. In addition, the various strategies required to construct effective functional materials for targeted cancer therapy are highlighted.