Objective · To prepare nanobowls, establish the method for characterizing nanoparticles, and test drug loading efficiency and release efficiency of nanobowls. Methods · The polystyrene nanoparticles (PSNPs) were prepared by the means of the normal emulsion polymerization. The peanuts nanoparticles (PNPs) were synthesized by the swelling process of PSNPs and the selective crosslinking between 3-(trimethoxysilyl) propyl methacrylate and tetraethylorthosilicate. Finally, the polystyrene was dissolved to obtain nanobowls. Dynamic light scattering (DLS) was used to analyze the size of each kind of nanoparticles. Transmission electron microscope (TEM) was used to observe the morphology of nanoparticles. Nanobowls loaded doxorubicin hydrochloride as a model drug though continuous shaking were used to measure drug loading capacity and release efficiency. Results · PSNPs, coated polystyrene nanoparticles (CPSNPs), PNPs, silica peanuts nanoparticles (Si-PNPs) and nanobowls were synthesized successfully. The size of nanobowls was (126.7±4.9) nm and the Zeta potential was (-30.2±1.1) mV. The final nanoparitcles could be used to load drug easily. The drug loading efficiency and loading capacity reached 51.1% and 9.3%, respectively. Moreover, the nanobowls had the expected sustained release effect. Conclusion · The prepared nanobowls are loaded with drugs successfully, which can release drug slowly and almost completely. The nanobowls can be used for drug release delivery.