This study was purposed to investigate the serum levels of soluble intracellular adhesion molecule (sVCAM-1), interleukin 18 (IL-18) and vascular endothelial growth factor (VEGF) in patients with aplastic anemia (AA) and their clinical significance. Enzyme linked immunosorbent assay (ELISA) was used to detect sVCAM-1, IL-18 and VEGF in serums of 30 patients with AA and 25 normal controls. The results showed that the serum levels of sVCAM-1 and IL-18 in patients with AA [(839.08 +/- 173.97) ng/ml, (380.35 +/- 47.76) pg/ml] were significantly higher than those in normal controls [(538.16 +/- 91.21) ng/ml, (256.39 +/- 59.52) pg/ml] (p < 0.01; p < 0.01). The levels of sVCAM-1 and IL-18 in severe AA patients [(969.94 +/- 182.54) ng/ml, (388.96 +/- 46.06) pg/ml] were higher than those in chronic AA patients [(709.26 +/- 165.32) ng/ml, IL-18 (352.21 +/- 47.08) pg/ml] (p < 0.01; p < 0.05), but the level of VEGF in AA patients [(69.63 +/- 27.42) pg/ml] was lower than that in the normal controls [(125.62 +/- 32.15) pg/ml] (p < 0.01)]. The level of VEGF in severe AA patients [(51.30 +/- 29.86) pg/ml] was significantly lower than that in chronic AA patients [(80.02 +/- 25.14) pg/ml] (p < 0.01). The levels of sVCAM-1 and IL-18 in AA patients after treatment were lower than those before treatment (p < 0.01; p < 0.05), but the level of VEGF after treatment was significantly higher than that before treatment (p < 0.05). It is concluded that the high levels of sVCAM-1, IL-18 and low level of VEGF in serum may be involved in the pathogenesis and progress of AA.