Gas analyzer and method of detecting state of gas analyzer

A gas analyzer includes: a column that separates a component in a sample gas; a valve that switches, between a test sample gas and a standard sample gas, the sample gas to be supplied to the column; a valve that adjusts an introduction amount of the sample gas to be supplied to the column; a detector that detects, by gas chromatography, the component in the sample gas separated by the column; and a control device. The control device controls the valve to allow the introduction amount to be a predetermined amount, calculates a peak area value of a chromatogram obtained by the detector when the introduction amount is the predetermined amount, and calculates a correspondence between the introduction amount and the peak area value.