Highly colloidal and asphaltic crude oil easily forms a water-in-oil emulsion with the water phase under the shear action of the throat, producing a liquid resistance effect and plugging the formation, resulting in a severe drop in well production. The flow law and liquid resistance effect of water-in-oil emulsion within a complex porous medium influenced by crude oil viscosity, water content, and the emulsion particle size/throat diameter ratio were investigated using indoor core replacement experiments and microscopic pore flow simulation techniques. The results demonstrated that the water-in-oil emulsion's liquid resistance effect increased with increasing water content, resulting in a rise in the beginning pressure gradient. For high-viscosity crude oils, crude oil viscosity has a stronger effect on the emulsion start-up pressure gradient, but for low-viscosity crude oils, the degree of matching of emulsion particle size to throat size has a bigger effect on the emulsion start-up pressure gradient. The droplet liquid resistance effect has a stronger influence on emulsion particle size than the throat shear effect, resulting in a progressive rise in the particle size of the water-in-oil emulsion as it flows through the porous medium. The liquid resistance effect increases seepage resistance when the capillary number of a water-in-oil emulsion decreases. The mechanism and influencing elements of the liquid resistance effect of water-in-oil emulsion in porous media are clarified in this research, which gives a theoretical basis for improving recovery in highly colloidal and asphaltene reservoirs.