The probe drive unit (21) collects a sample (8) at the tip of the probe (6) by lowering and raising the probe (6) under the control of the control unit (25). After that, the high voltage generating unit (20) applies a high voltage whose voltage value increases in a slope shape to the probe (6), and meanwhile, the mass spectrometry unit behind the capillary tube (10) performs product ion scan measurements on the two-step probe voltage, and the mass spectrum data obtained in each measurement is stored in the first and the second probe voltage corresponding data storage units (301 and 302). When the ionization efficiencies of the plurality of types of components contained in the sample (8) have a probe voltage dependence, ion peaks derived from different types of components appear in the two mass spectra. Thus, a plurality of types of components contained in the sample can be roughly separated, and the identification performance based on the mass spectrum and the quantitative performance based on the chromatogram can be improved.