Abstract: In order to study the decomposition characteristics of trifluoromethyl sulfonyl fluoride (CF₃SO₂F) and its gas mixtures, we carried out corona discharge tests using needle-plate electrodes. Based on gas chromatography-mass spectrometry (GC/MS) technology, CF₃SO₂F pure gas, CF₃SO₂F and 40%CF₃SO₂F/N₂ decomposition by-products were detected. Then, the decomposition path of CF₃SO₂F and the formation of the main decomposition by-products were analyzed by the quantum chemistry theory. The experimental results show that the decomposition by-products of CF₃SO₂F mainly include CO₂, CF₄, C₂F₆, C₂F₆O₃, SO₂, SOF₂, and SO₂F₂ under corona discharge which are the same as those of mixed gases, and no products containing element N are found. The calculated results show that CF₃SO₂F will be cleaved to produce F—, O, CF₃— and CF₂ free radicals. CF₄ and C₂F₆ are primarily formed from the initial decomposition of CF₃SO₂F, which generates CF₃— free radical. The composite process is a one-step reaction that does not require activation energy and releases energy to the surroundings. The formation of C₂F₆O₃ is mainly related to O₂, CF₃— and O. The formation of sulfur compounds such as SO₂, SOF₂, and SO₂F₂ requires multiple cracking and recombination. This study can provide references for the decomposition characteristics of CF₃SO₂F and the reasons for product formation.