There are different defects in current theory of legal interest judgment of data crimes.The core problem is that the existing theory believes that the legal interest of data crimes is single-layered.The structure of data is"carrier-data-information content",so the legal interest of data crimes should adopt a multi-layered struc-ture.Data crimes first infringe on data security,and then infringe on the legal interest of information content.Double legal interests theory can play the function of imagination competition and reduce the phenomenon of confu-sion in the identification of the number of crimes.Dual legal interest theory can play the function of interpretation and guidance of legal interest,accurately identify the nature of data crime,and reduce the phenomenon of different identification of similar criminal behavior.