The invention discloses a method of producing graphene by stripping graphite via time-space-synchronous ultrasonic treatment and a ball-milling process. The method includes the steps of: adding a graphite raw material and a stripping reagent into an ultrasonic ball milling device and performing ball milling for 2-96 h under an ultrasonic environment; and separating, washing and drying the mixtureto obtain graphene powder. Through the time-space-synchronous ultrasonic treatment and the ball-milling process, the graphite is stripped; due to the synergistic effect of the two methods, interlayerin-situ expansion of the graphite is formed and meanwhile a strong shear force is applied to the graphite during ball milling. The method is high in efficiency and yield and is suitable for large-scale production of graphene.