Aim T0 investigate the effects of phorbol myristateacetate (PMA) and some pathogenic factors in Dia-betes mellitus, such as high glucose (HG), high in-sulin (HI), high proinsulin (HPI) and tumor necrosisfactor-α (TNF-α) on free calcium ion in human umbili-cal vein endothelial cells (hUVEC).Metbods To detect calcium ion concentration byfluoresent probes and con focal microscopy in thisstudy.Results HG,HPI and TNF-Q could elevate intracel-lular free calcium ion concentration ([Ca²⁺ ]i) in hU-VEC obviously while HI did not (p<0. 01 ). Under adynamic observation of ([Ca²⁺ ]i) and intranuclear freecalcium ion concentration ([Ca²⁺ ]n) in a single en-dothelial cell (EC) induced by HG, HPI, TNF-α andPMA. we found an ohvious ascent of [Ca²⁺ ]i and[Ca²⁺]n especially in nucleus area. We also observedthat TNF-α and HI could induce calcium oscillation inhUVEC, and PMA at high dose caused evacuation ofCa²⁺ which was most obvious in nucleus area-Conclusion In vascular complications of diabetesmany pathogenic factors injured vascular endothelialcells by Ca²⁺ signaling and thus led to the damage ofnormal vascular function and structure.