Objective Introduction modern personal healthcare and pharmaceutical industries have raised new concepts and requirements for the therapy of diseases: the abnormal cells can be cured with high efficacy while the progress of diseases can be monitored by external clinical imaging modalities.Nano-biotechnology has been introduced into theranostic field to achieve this goal by the advanced nano-synthetic chemistry.Mesoporous silica-based nanotheranostics exhibit the excellent performance in the nanomedical applications due to their excellent biocompatibility, large surface area, high pore volume, controlled pore sizes and abundant inner/outer surface chemistry.Herein, we would like to introduce our recent results about employing multifunctional mesoporous silica based nanotheranostic for drug delivery, molecular imaging and high intensity focused ultrasound (HIFU) cancer surgery.Results (1) To explore the alternatives to substitute cytotoxic Gd(Ⅲ)-based contrast agents for T1-weighted magnetic resonance imaging(MRI), we used manganese-based agents with similar MRI-T1 performances to commercial Gd-based agents by introducing MnOx nanoparticles into the mesoporous by the in-situ redox reaction between surfactants and MnO-ions using mesopores as the nanoreactors.This synthetic strategy was based on the large surface area and tunable pore sizes to disperse Mn paramagnetic centers to increase the accessibility of water molecules to the Mn centers, which is very important to improve the performances of MRI-T1 contrast agents.Systematic investigations of the in vitro and in vivo capabilities of such manganese-based nanotheranostic agents have been carried out.Meanwhile, the penetrating mesoporous present in the whole matrix endows such multifunctional nanotheranostics with the capability of drug encapsulation and intracellular delivery, which was demonstrated by using doxorubicin as the model chemotherapeutic agents for in vitro and in vivo drug transportations.(2) We have introduced nano-biotechnology into the non-invasive cancer surgical field for the first time by using engineered multifunctional mesoporous composite nanocapsules (MCNCs) for MRI-guided high intensity focused ultrasound (HIFU).On the one hand, the manganese decorated multifunctional mesoporous shells could be used as the contrast agents for MRI-T1 to visualize the tumor tissue for further focused ultrasound positioning.On the other hand, the large hollow interiors could be used as the reservoirs for the encapsulation and delivery of PFH molecules for HIFU synergistic therapy.Such experimental evaluations have been performed systematically in vitro and in vivo.The results showed that the introduction of MCNCs could significantly enhance the tumor MRI-T1 to make the boundary between tumor and normal tissues much more clearly.Upon the HIFU irritation, the ablated tumor volume was substantially larger than the controlled experiments, demonstrating the synergistic therapeutic effect.Importantly, the mesopores could store and deliver chemotherapeutic agents for combined HIFU and chemotherapy.Conclusion We have introduced nano biotechnology into drug delivery, molecular imaging and HIFU surgery by engineering mesoporous silica-based nanotheranostics.These multifunctional nanotheranostics would greatly contribute to the progress of protocols for efficient cancer diagnosis and therapy.