A confined space quantitative evaluation method of vapor phase corrosion inhibitors was put forward based on summarization of foreign and domestic literature on vapor phase corrosion inhibitors evaluation. The test conditions of the method were optimized through experiments. The results showed that the best experimental conditions are as follows: the experimental temperature is 60 ℃; the cycle period is 8 h heating and 16 h staying; and the experimental time is one day(24 h). In the experiment, 60 mL electrolyte solution with the same 1 g/L mass fraction of NaHCO-3, Na-2SO-4 and NaCl was used. This quantitative evaluation method was verified by test on one-component corrosion inhibitors and available compound corrosion inhibitors. The purpose was to provide reference for vapor phase corrosion inhibitors evaluation.