Provided is a gas chromatograph including a column which separates a sample; a detector which is configured to alternately introduce a carrier gas containing a sample component separated by the column and a carrier gas alone into a detection unit by changing an inflow point of the carrier gas to acquire a signal; an analysis information input unit with which analysis information is input; a data retaining unit which retains data indicating a relationship between a column flow rate and a carrier gas flow rate which is obtained in advance; and calculation unit which is configured to calculate the carrier gas flow rate on the basis of the analysis information input from the analysis information input unit and calculate the carrier gas flow rate according to the calculated column flow rate by using the calculated column flow rate and the data retained in the data retaining unit.