The invention discloses an experimental test method for gas reservoir reverse imbibition water blocking damage evaluation under a high-temperature and high-pressure condition. The experimental test method is completed through a water blocking effect experimental measuring device. The experimental test method comprises the steps that firstly, a core is washed and dried to be placed into a core holding unit; secondly, the core is vacuumized, displacement pressure is increased to formation pressure Pf, and formation water is injected into the core under constant pressure; thirdly, the temperature is raised to the formation temperature T0; fourthly, nitrogen is injected into the core, displacement is carried out until the liquid level of a water measuring meter at the core outlet end does not change, and gas phase permeability K1 is calculated; fifthly, formation water is injected into the core until no gas is discharged out of the core outlet end; sixthly, secondary gas driving water is carried out on the core, displacement is carried out until the liquid level of the water measuring meter at the core outlet end does not change, and gas phase permeability K2 is calculated; seventhly, the damage degree of water blocking damage to the gas phase permeability is determined. The experimental test method conforms to the actual gas reservoir developing process, a reasonable testing method is provided for reservoir water blocking damage measuring evaluation, and the experimental test method has wide market prospects.