This paper conducts an experimental study on the variation law of material volume resistivity in a multi-physics field environment. Firstly

an experimental system under the combined action of pressure

temperature

relative humidity and electric field is established. Then

the volume resistivity response characteristics of typical non-metallic materials are analyzed. The experiment results show that the volume resistivity of non-metallic materials decreases with the increase of electric field intensity

and the reduction amplitude remains one order of magnitude within the range of the experimental electric field intensity. The volume resistivity of non-metallic materials decreases by 2 to 4 orders of magnitude with the increase of temperature. Under humidity conditions

the volume resistivity of the material significantly decreases due to water penetration and ion dissociation. The percolation threshold appears in the range of 40%~60% relative humidity (RH)

and the pressure synergy effect further reduces the percolation threshold. Pressure reduces volume resistivity by compressing the band gap

but its influence amplitude (< one order of magnitude) is weaker than that of temperature and relative humidity. In the coupling of multiple physical fields under experimental conditions

the influence weights of temperature and relative humidity on volume resistivity are significantly higher than those of pressure

and the synergistic effect of high temperature-high pressure or high humidity-high pressure will accelerate the decrease of resistivity. This research provides a crucial basis for the material selection design and performance evaluation of equipment in complex environments.