AIM To investigate the effects of collagen solution on the prevention of acute gastric mucosal injury inrestricted rats inflicted by cooling in low temperature (4℃),METHODS Thirty healthy Wistar rats were randomly divided into normal (N, n = 10),injury (I, n = 10)and prevention (P, n = 10) groups. The rats were fasted for 48 h but free access to water without restrictionand cooling in normal group, fasted for 48 h but free access to water with restriction of rats onto the fixationframe for cooling in 4℃ for 4 h, so to cause stress injury of gastric mucosal membrane in I group and fed with3 mL of collagen solution 30min before injury in P group in addition to the procedures in I grobp. Gastricmucosal potential difference, blood flow volume, content of nitrite (NO2-) and hydrogen ion concentration(H+ ) in gastric juice were determined under aneasthesia at 48 h after fast in N group and at 4 h after injuryin I and P groups to evaluate the degree of injury (injury index).RESULTS Gastric mucosal potential difference was 22.10±5.27 in N group and 11.46±5.25 in I groupwith obvious difference (P<0.01), but 16.98±4.84 in P group which was remarkably improved whencompared to that in I group. Gastric mucosal blood flow volume was 23.65±10.65 in I group and 57.20±11.75 in N group with evident difference (P<0.01), but 37.49±5.87 in P group with sound effects incontrast to that in I group (P<0.01). Gastric injury index was 18.40±8.35 in I group and 7.9±2.13 in Pgroup with significant difference (P<0.01). Hydrogenion concentration in gastric juice was 118.0±41.2mmol/L in N group, 186.9±74.7 mmol/L in I group and 96.4±57.2 mmol/L in P group with prominentdifference (P< 0.01 ) between those in I and P group. Gastric mucosal nitrite concentration was 1.15±0.46in N group, 0.69±0.15 in I group and 1.04±0.44 in P group with obvious differences between N and Igroups (P<0.01) and between I and P group (P<0.01).CONCLUSION Ischemic and hypoxic injury of gastric mucosal due to low blood perfusion during restrictionand cooling injury at 4℃ was supposed to be an important factor in inducing gastric mucosal stress injury. Butcollagen solution could maintain the integrity of gastric mucosal barrier, buffer gastric acid, promotethrombocytic agglutination and ameliorate direct injury to gastric mucosa caused by various factors.