Objective To explore the construction and application effects of sub-specialty nursing for gastrointestinal poisoning. Methods According to the specialty characteristics of gastrointestinal poisoning nursing and the principles of hospital treatment,a sub-specialty nursing group of gastrointestinal poisoning was established in January 2022,and the organizational structure,quality control methods,work contents,standard procedures and training programs were formulated. The changes of nurses‘ clinical comprehensive practice ability,specialty theory and specialty skills,time node parameters of nursing measures implementation and main outcome indicators of patients were compared before and after the establishment of subspecialty nursing group of gastrointestinal poisoning. Results The clinical comprehensive practice ability,specialty theory and specialty skills of nurses were significantly improved after the establishment of subspecialty nursing group of gastrointestinal poisoning（P<0.001）. For time node indicators of implementation of nursing measures for patients with acute gastrointestinal poisoning,the start time of ECG monitoring was shortened by about 2 min（P=0.005）,the blood sample collection time was shortened by about 5 min（P<0.001）,the start time of hemoperfusion was shortened by about 30 min（P=0.029）,the interval of perfusion was shortened by about 17 min（P=0.001）,and the start time of intravenous medication was shortened by about 2 min（P=0.005）,the beginning time of antidote use was shortened by about 36.5 min（P<0.001）. The collection time of urine sample,the start time of gastric lavage and the start time of catharsis all showed a shortening trend,but the differences were not statistically significant（P>0.05）. For the main outcome indicators of patients,the survival rate at 7 days was increased by about 8%（P=0.024）,and the survival rate at 28 days was increased by about 8%（P=0.045）. For secondary outcome measures,the length of stay in general ward was shortened by about 1 days（P=0.008）,and the length of stay in ICU was shortened by about 3 days（P=0.029）. There was a trend of shortening of the stay time in emergency room,but the difference was not statistically significant（P>0.05）. Conclusion The construction of sub-specialty nursing of gastrointestinal poisoning can effectively improve nurses‘ ability of specialized nursing practice and improve nursing quality of patients with gastrointestinal poisoning.