The soluble form of the vascular cell adhesion molecule-1 (VCAM-1) is detectable in human sera and is elevated in diabetic patients, with unknown clinical significance. In the present study, the relationship between serum soluble VCAM-1 and diabetic microvascular complications (retinopathy, nephropathy, and neuropathy) was evaluated in 95 Japanese patients with Type 2 diabetes mellitus (DM). Serum soluble VCAM-1 concentration was higher in patients with more advanced stages of retinopathy as well as nephropathy. There was a significant correlation between soluble VCAM-1 and log10 (urinary albumin excretion) in 69 patients with normal serum creatinine levels (r = 0.51, p < 0.0001) and a significant correlation between soluble VCAM-1 and log10 (serum creatinine) in all the patients (r = 0.83, p < 0.0001). Soluble VCAM-1 concentration was also elevated in patients with neuropathy. There was a significant correlation between soluble VCAM-1 concentration and the number of microvascular complications (r = 0.59, p < 0.0001). However, multivariate regression analysis revealed that only diabetic nephropathy, was associated with the soluble VCAM-1 concentration. The elevation of circulating VCAM-1 level in diabetic nephropathy may result from underlying systemic endothelial dysfunction, increased VCAM-1 production in damaged renal tubular or glomerular epithelial cells and/or decreased renal clearance of this molecule, depending on the stage of nephropathy.