The Qvod case in 2016, in which the Chinese video-sharing site Qvod was convicted of the crime of disseminating pornographic materials for profits, provoked heated debates regarding the criminal responsibility of internet service providers (ISPs) in China. Using the Qvod case as an example, this paper first discusses the definition and the legal obligations of ISPs, and argues that we should decide the criminal responsibility of ISPs according to their functions and the content of their services. This paper further analyzes four major issues associated with the criminal responsibility of ISPs, including accomplice responsibility, accessory with neutral conduct, perpetrator by action or omission and ideal concurrence (Idealkonkurrenz).