Early diagnosis of cancer is still a major challenge in cancer therapy. In recent years, the development of multifunctional nanomaterials has provided a new diagnosis and treatment platform to combat cancer. Polymer-inorganic nanomaterials with novel structures such as bowl-shaped/Janus/core-shell have drawn much attention owing to their diversity in composition or asymmetry in structure. More importantly, imparting unique optical, electrical, and magnetic properties to these nanocomposites can further extend their function repertoire. However, to fulfill this vision, fundamental understandings regarding strategies of precise synthesis, mechanisms of structure formation, in vivo synergistic effects in bioapplications, and biosafety of these materials are needed. Besides, nanomaterials with novel structures are well positioned for imaging-guided cancer theranostic. On one hand, nanomaterials themselves are suitable for imaging because of their intrinsic properties such as fluorescent or magnetic properties. On the other hand, nanomaterials can serve as functional platforms that integrate various therapeutic modalities including photothermal therapy, chemodynamic/ion-interference therapy, photodynamic therapy, and cuproptosis to efficiently kill cancer cells. This Research Topic aims at collecting works about synthesis, and biomedical applications of polymer/mesoporous inorganic nanomaterials, especially in the aspect of novel synthetic approaches for fabricating nanomaterials with unique structures. Additionally, we hope that in-depth research articles on this topic can provide insights into the mechanism of nanomaterials acting in cancer diagnosis and therapy. These include the mechanisms of customized drug load/release and synergistic effects in theranostics of these materials. Meanwhile, elucidations of key proteins’ roles in cancer development are also anticipated. Lastly, we hope that this topic can brew new ideas for the adaption of nanomaterials as platforms that allow for multimodal therapeutic modalities. The current Research Topic centers on the design, precise synthesis, and biomedical applications of nanomaterials. It aims to cover novel and promising research trends in nanomaterials with different morphology for cancer theranostics. Manuscripts from the following aspects, but not limited to, are welcomed: • Tailoring of asymmetrically structured (bowl-shaped, Janus, Yin Yang-like) polymer-inorganic nanomaterials; • Inorganic functional nanocrystals and functionalized mesoporous nanomaterials; • Design and synthesis of functional biomaterials, including lipids, polymers, and 2D materials • Non-viral DNA/mRNA delivery or drug/molecular inhibitor delivery; • Synthesizing biomaterials with novel nanostructures such as bowl-shaped, core-shell, spherical, Janus, and quantum dots; • Conquering drug resistance issues, tumor metastasis, and recurrence, as well as designing combination nanomedicines; • Dissecting the role of menin in prostate cancer and breast cancer: crosstalk between menin and AR signaling; • Multi-stimulus-responsive drug release and biological molecules.