Information technology has led the society into the digital age, and has produced various ways of communication, which has made great changes in citizen life. E-mail, Tencent QQ, micro-blog, WeChat and other border information transmission channels have been gradually used by people, forming a huge exchange circle. While this huge exchange circle is running, we must pay attention to both sides of things. Communication fraud, phishing websites and so on, the modern and emerging forms of crime are increasingly emerging, and emerge in an endless stream, and spread to wider areas. Electronic data become an important role in these criminal cases. The exploratory judicial system of electronic data evidence complies with the inevitable trend of the changes of the times, and has a profound influence on perfecting our legal system and enriching our judicial practice. This paper, aiming at the application of electronic evidence in criminal cases, analyzes the content of electronic evidence, clarifies the role of electronic evidence in the criminal field, combined with the current situation of legislation and practice in China, and draws on the relevant legislation and practice of foreign countries to further explore the significance of the existence of electronic evidence in the criminal field of our country.