Mass analysis system, and method for determining performance of mass analysis device

A mass analysis system, comprising:

• a mass analysis device including an ion source configured to ionize a measurement sample, a mass analysis unit configured to analyze ions generated by the ion source in accordance with a mass-to-charge ratio, and a detector configured to detect ions having passed through the mass analysis unit;
• a first converter configured to calculate a first measured value based on an intensity and an area of a pulse in an electric signal output from the detector;
• a second converter configured to obtain a second measured value by counting the number of pulses of the electric signal;
• a calculation unit configured to calculate an A/P ratio indicating a ratio of the first measured value to the second measured value;
• a determination unit configured to determine a performance of the detector based on a value of the A/P ratio;
• and
• a control unit configured to control at least an output of a determination result obtained by the determination unit.