Abstract: Compared with illegal data transfer，illegal use of data is original and direct. But it is unable to be covered by the charges of current criminal law in China，nor can it be effectively regulated by other laws. To make amends for the loophole of criminal punishment，the incriminating process of illegal use of data should be advanced. Firstly，the crime of illegal use of data should maintain the same standard as the existing crime of breaching data security，which conforms to the legality attribute. Secondly，the“illegal use”should include not only the conduct of using data without the permission of data subject，but also the conduct of using data，after lawful collection of data with the consent of the data subject，in violation of the aforementioned rules，purpose，manner，and scope. Thirdly，the“circumstances of aggravation”should be comprehensively judged in reference to the gravity of the circumstances of illegal data transfer，together with the damage of illegal use of data，and the type and quantity of behavior. Finally，cases in the public interest and the legitimate interest of data controller should be upheld as the decriminalizing causes of the crime.

Key words: data crime；illegal use of data；data security