Vascular endothelial growth factor receptor 1 (VEGF R1), also known as Flt-1, is a specific tyrosine kinase (RTK) receptor for angiogenic factors VEGF (VEGF-A), placental growth factor (PIGF), and VEGF-B. According to the shear form, there are two forms: membrane type (mbVEGFR) and soluble type (sVEGFR). Experimental and clinical injection of sVEGF R1 successfully prevented angiogenesis and tumor growth. The levels of sVEGF R1 in serum/plasma vary under different pathological conditions, which may have diagnostic value. Under experimental and pathological conditions, sVEGF R1 is correlated with VEGF levels. There are high levels of sVEGF R1 in the plasma of pregnant women and patients with primary hypertension. The levels of sVEGF R1 in the plasma of cardiovascular disease patients and smokers were significantly reduced.