The invention discloses a visualization experiment system and method for measuring a representation contact angle under high temperature and high pressure environments. The visualization experiment system is characterized by comprising an air distributing device, a testing device, a sampling device, a vacuum device, a pressure regulating device, an optical imaging device and a monitoring device, and mainly consists of the equipment such as an air compressor, a high pressure gas cylinder, a gas pressurizer, a high pressure buffer container, a reducing valve, a mechanical pressure gauge, a hightemperature and high pressure visual container, a pressure transmitter, a one-way control valve, a micrometeor high pressure plunger pump, a cold light source, a vacuum pump, a vacuum buffer container, a temperature controller, a condenser, a back pressure valve, a CCD camera, an image analyzer and the like. The measurement of the contact angle under high temperature and high pressure environments, even in a super-critical state of water, can be realized, and the system is particularly applicable to infiltration behavior research of water on a metallic surface under high temperature and high pressure environments. The visualization experiment system has the advantages of high working condition parameters, wide application range, convenient and flexible operation, long service life, convenience in expansion and modification and the like.