In a simultaneous multicomponent analysis for a number of target compounds, an MRM transition which does not give the highest signal intensity but gives a lower signal intensity is selected for a compound having a high measurement sensitivity or a compound having a high measurement target concentration. If the signal intensity is still high, the level of collision energy (CE) is changed from an optimum level. The MRM transition, CE level and other measurement conditions determined for each compound in this manner are stored in a compound-related information storage 41. In the process of preparing a control sequence for the simultaneous multicomponent analysis, the measurement conditions stored in the storage section 41 are used. The use of those conditions prevents the saturation of the signal for a high-concentration compound while ensuring a sufficiently high level of sensitivity for a low-concentration compound.