Abstract: Posterior capsule opacification (PCO) is the frequent complication after cataract surgery. Transforming growth factorβ (TGFβ) is the important growth factor to modulate the transdifferentiation and formation of extracellular cell matrix (ECM) of cells. TGFβ modulates the proliferation, epithelialmesenchymal transition and the formation of ECM by Smad signaling pathway. The research progress of TGFβ/Smad signaling pathway in PCO is reviewed in this article.