With the continuous development of modern science and information technology

cloud computing and big data not only bring more convenience to modern people’s life

but also pose a great threat to personal information security. Based on this

this paper first expounds the application advantages of big data and cloud computing technology

then analyzes the current situation of collaborative protection of personal information security under the environment of big data and cloud computing

and finally it focuses on the relevant information security technology

in order to provide a certain guarantee for personal information security in the era of cloud computing and big data in China.