Abstract: So far, polygalacturonase_inhibiting protein(PGIP) has been discovered in 20 species of plants. PGIP is primarily localized in the cell wall and endoplasmic system, but the levels of PGIP in different varieties, organs, or growth phases are different, and these differences are closely related to plant resistance. PGI P is an inhibitor of endo_PG from fungi, thus refrain plant from fungal infection. The experimental dada from Phaseolus vulgaris L. and Triticum aestivum L. indicate that the level of pgip gene transcription and translation is closely related to fungal infection, but this mechanism need further study.