The invention provides a method for testing the flow resistance of a dispersion system under high temperature and high pressure conditions. The method comprises the following steps of: step A, inducing a displacing agent for displacing into a multiphase fluid disperser to form a uniformly distributed dispersing system by experimental equipment comprising the multiphase fluid disperser in a displacing experiment; step B, inducing the uniformly distributed dispersing system into a micro tube to displace an agent to be displaced in the micro tube, wherein the internal diameter of the micro tube is less than or equal to 250 micrometers; and step C, observing and recording the pressure difference between an inlet end and an outlet end of the micro tube until the pressure difference is qualified, and then calculating the flow resistance according to the qualified pressure difference Zf=delta P/QL, wherein when the pressure difference fluctuation range is within +/-5%, the pressure difference is determined to be qualified, and Zf equals to the flow resistance.