To establish a method of comparing record CCD camera’s performance in ultrafast optic diagnostic systems (e.g. streak cameras, frame cameras based on gated micro channel plate intensifier, etc.), the CCD camera’s main performance parameters were compared and discussed. It is the analyzing result that CCD camera’s lower detectable limit and dynamic range both are the most important aspects of these systems. Two rules that can ensure one comparing different CCD cameras’ performance without installing them onto a virtual system were introduced. First, the pixel group associated with the minimal resolvable element of the system should be treated as a unit so that the CCD cameras with different pixel number and different pixel size can be compared fairly. Second, the minimal detectable optic power and the optic dynamic range are both chosen to be the appropriate parameters for evaluating the performance among CCD cameras with different digital levels and output fluctuations. A demonstration system for evaluating different CCD cameras offline was constituted where a scientific grade CCD camera and an EMCCD camera were tested. Compared with the scientific grade CCD camera, the EMCCD camera’s minimal detectable optic power is lower and its dynamic range is wider. The method was successfully applied in the constitution of the ultrafast optic diagnostic system for Zpinch.