Abstract: Pectin methylesterase inhibitor（PMEI） plays an important role in the process of plant stress resistance.In order to explore the biological function of MePMEI1 in cassava and its role in protein interaction network, in this paper, the bait vector pGBKT7-MePMEI1 was constructed in cassava and the interaction proteins of MePMEI1 were screened in cassava c DNA library by yeast two-hybrid. The results showed that a total of 57 positive clones were screened, and the positive rate was about 32.6%. About 37 kinds candidate interaction proteins with complete open reading frame（ORF） were identified by sequencing, including non-specific serine/threonine protein kinase, threonine specific protein kinase, chlorophyll a/b binding protein, voltage dependent anion channel protein2（VDAC2）, nitrogen regulatory protein, xyloseglucose transferase（TCH4）, Glyoxalase-2 protein, etc. The authenticity of protein interaction was verified by rotary verification. The results showed that MePMEI1 interacted with VDAC2, glyoxalase-2 protein, which further supplemented its protein interaction network, and provided new evidence for exploring the interaction network of MePMEI1 protein.