OBJECTIVE: This study aimed to investigate the biological factors associated with baseline peritoneal transport in uremic patients before dialysis. METHODS: Thirty patients with uremia were grouped according to their peritoneal dialysate creatinine/serum creatinine ratio (D/P) as high-transport (H, 16 cases) with D/P>0.65 and low-transport (L, 14 cases) with D/P≤0.65 one month after continuous ambulatory peritoneal dialysis treatment. Multi-inflammatory levels such as serum IL-6 and albumin, peritoneal IL-6 level, and microvessel density (MVD) of visceral peritoneal were compared and correlated between the two groups to determine the associated factors. RESULTS: There were no significant differences in clinical parameters between the two groups (p < 0.05). There were no significant differences in serum IL-6 and albumin between the two groups. However, peritoneal IL-6 and MVD in group H were significantly higher than group L (p=0.012, p=0.044), and they were positively correlated (r=0.368, p=0.045). Furthermore, baseline D/P was positively correlated with IL-6 expressions (r=0.640, p=0.000) and peritoneal MVD (r=0.476, p=0.008), and independently associated with peritoneal IL-6 expression (p=0.004). CONCLUSIONS: The baseline peritoneal transport performance is associated with peritoneal IL-6 expression and MVD but not circulatory IL-6.