Disclosed is an ICP light-emitting spectral analysis apparatus. Provided is an advance of photomultiplier tube voltage to quickly transferred to the main analysis ICP light-emitting spectral analysis apparatus. An ICP emission spectrometer (1) is schematically configured to include an inductively coupled plasma generation unit (10), a light condensing unit (20), a spectroscope (30), a detector (40), and a controller (60). The detector (40) includes a photomultiplier (70) and has a detector controller (41) and an input unit (42). The photomultiplier (70) has voltage dividing resistors r1-rn, which make an amplification factor not to become constant immediately due to a change in an application voltage applied to the photomultiplier (70), but the detector controller (41) controls an idle voltage and an idle voltage application time so that a multiplication factor becomes constant, during a period from when analysis conditions are input to the input unit in advance until a sample containing an analysis-targeted element is introduced into the inductively coupled plasma generation unit (10).