Cancer therapy is popularly filed in recently years. Doxorubicin is mainly chemotherapy drug that has effective in cancertreatment, including breast cancer, lung cancer and colorectal cancer. Although the patients have been cured but thesechemotherapy drug can cause severe side effect, such as cardiac toxicity and myelosuppression. Nanoparticles are available toeliminate side effect because it has the enhanced permeability and retention effect that could accumulate nanoparticles in thetumor site. Nanopaticles are composed of liposome, carbon nanotube, gold nanoshell and protein nanocage. Protein nanocage isa promising nanocarrier since it has biological compatibility and biodegradability. In this study, we utilized apoferritin nanocageto encapsulate hydrophilic drug doxorubicin to treat colorectal cancer. We demonstrated that apoferritin were pH sensitiveprotein that could disassemble in lower pH and reassemble in neutral pH conditions. The hydrophilic drug doxorubicin hadhigh encapsulated efficiency approximately 48%. The apoferritin could also encapsulate similar physical properties chemicalagent and released out of nanocage in lower pH conditions. In cytotoxicity, we used colorectal cancer cell. The cancer cell hadsuccessful killed in 24 hours in a dose-dependent manner and more severe cytotoxcity in 48 hours. In the future, it is a promisedrug delivery platform to load chemotherapy drug.