Effects of four insecticides on intestinal mucosa permeability of the wolf spider (Pardosa pseudoannulata) were studied by exposing spiders to insecticides and then measuring the concentration of fluorescein isothiocyanate-dextran (FITC-D) in the spiders’blood. The results showed that FITC-D concentrations of the test groups were much more than that of the control group. The difference between the test groups and the control group was statistically significant. It could be deduced that all the insecticides tested in this experiment damaged the spiders′ intestinal mucosa, compromising its function as a barrier and letting large molecules such as FTIC-D more easily penetrate. Among the insecticides, pyrethrin and Bt (Bacillus thuringiensis) preparation are bio-insecticides, and the FITC-D concentrations of the spiders exposed to these two bio-insecticides were more than those of the spiders exposed to the chemical insecticides imidacloprid and dipterex. The difference between the bio-insecticide groups and the imidacloprid group was significant, but there was no significant difference between the bio-insecticide groups and the dipterex group. Despite the damaging effects of insecticide exposure, the spider intestinal mucosa is resilient, to a certain extent. In spiders exposed to the insecticide only once, the barrier function of their intestinal mucosa was shown to recover within 6-10 days at times.