In order to be able to prevent analysis accuracy from being reduced by a backward flow of sample gas from dead volume in a cleaning mechanism into a cell at the time of analysis, a gas analysis device has an analysis part that analyzes the sample gas introduced into the cell, gas ports that are arranged toward predetermined regions of gas contact surfaces in the cell, and a piping mechanism that connects the gas ports to a predetermined purge gas source, and blows purge gas from the gas ports toward the predetermined regions at the time of purging. The gas analysis device also has a switching part that switches a connecting destination of the piping mechanism from the purge gas source to a predetermined suction part, and at the time of introducing or analyzing the sample gas, connects the gas ports to the suction source.