Worldwide digital reading rates are growing rapidly, digital reading has become a habitual media use behavior in people's lives. While digital medium provide information and knowledge immediacy, convenience and interactivity, it has been criticized for the entertainment tendencies, extensive superficiality, and intellectual illusions. Cultivating readers' digital deep reading ability is conducive to promoting the development of individuals and countries. As we are not born to read, digital reading is an acquired ability. Digital deep reading is the advanced stage of reading form, which is more conducive to the utilization, reflection and creation of information than extensive reading. The formation of deep reading in the digital media environment is closely related to the activeness, engagement and intellectual participation of the subject, and is affected by the reading scene, content, motivation, and efficacy. This paper adopts qualitative and quantitative research methods, observes skilled digital deep reading behaviors, summarizes the strategies of digital deep reading, and discovers the important factors that affect digital deep reading. It aims to establish a behavioral cognitive model of digital deep reading, provide theoretical basis for individual reading practice, group reading activities intervention, and enrich the disciplinary horizon and theoretical perspective of reading research.