To compare effects of different resuscitation fluid on microcirculation, inflammation, intestinal barrier and clinical results in severe acute pancreatitis (SAP). One hundred and twenty patients with SAP were enrolled at the Pancreatic Disease Institute between January 2007 and March 2010. The patients were randomly treated with normal saline (NS group), combination of normal saline and hydroxyethyl starch (HES) (SH group), combination of normal saline, hydroxyethyl starch and glutamine (SHG group) in resuscitation. The ratio of normal saline to HES in the SH and SHG groups was 3:1. The glutamine (20% glutamine dipeptide, 100 mL/d) was supplemented into the resuscitation liquid in the SHG group. Complications and outcomes including respiratory and abdominal infection, sepsis, abdominal hemorrhage, intra-abdominal hypertension, abdominal compartment syndrome (ACS), renal failure, acute respiratory distress syndrome (ARDS), multiple organ dysfunction syndrome (MODS), operation intervention, length of intensive care unit stay, length of hospital stay, and mortality at 60 d were compared. Moreover, blood oxygen saturation (SpO2), gastric intramucosal pH value (pHi), intra-abdominal pressure (IAP), inflammation cytokines, urine lactulose/mannitol (L/M) ratio, and serum endotoxin were investigated to evaluate the inflammatory reaction and gut barrier. Compared to the NS group, patients in the SH and SHG groups accessed the endpoint more quickly (3.9 ± 0.23 d and 4.1 ± 0.21 d vs 5.8 ± 0.25 d, P < 0.05) with less fluid volume (67.26 ± 28.53 mL/kg/d, 61.79 ± 27.61 mL/kg per day vs 85.23 ± 21.27 mL/kg per day, P < 0.05). Compared to the NS group, incidence of renal dysfunction, ARDS, MODS and ACS in the SH and SHG groups was obviously lower. Furthermore, incidence of respiratory and abdominal infection was significantly decreased in the SH and SHG groups, while no significant difference in sepsis was seen. Moreover, less operation time was needed in the SH and SHG group than the NS group, but the difference was not significant. The mortality did not differ significantly among these groups. Blood SpO2 and gastric mucosal pHi in the SH and SHG groups increased more quickly than in the NS group, while IAP was significantly decreased in the SH and SHG group. Moreover, the serum tumor necrosis factor-α, interleukin-8 and C-reactive protein levels in the SH and SHG groups were obviously lower than in the NS group at each time point. Furthermore, urine L/M ratio and serum endotoxin were significantly lower in the SH group and further decreased in the SHG group. Results indicated that combination of normal saline, HES and glutamine are more efficient in resuscitation of SAP by relieving inflammation and sustaining the intestinal barrier.