Background: Gastrointestinal decompression through ileus tube is useful for the treatment of adhesive small bowel obstruction (ASBO). Gastrogra n administration through the ileus tube is performed if decompression therapy fails to relieve obstruction. However, the e cacy and appropriate timing of gastrogra n administration are unclear. This study aimed to evaluate the e cacy of gastrogra n administration within 48 h after admission. Methods: This retrospective study used the data of patients with ASBO admitted to our hospital between January 2014 and August 2018 and included those who underwent ileus tube intubation but did not achieve obstruction relief for over 24 h after admission. The patients were classi ed into the following two groups: those treated with gastrogra n administration within 48 h after admission (EGA group) and those treated without gastrogra n administration within 48 h after admission (non-EGA [NEGA] group). Propensity-score matching was performed to compensate for confounding differences between the groups. The short-term outcomes including the rate of successful conservative management without surgery, the period until the rst stool, the period of ileus tube intubation, the total period of hospital admission, and adverse events due to gastrogra n administration were evaluated and compared between the two groups. Results: This study included 152 patients: 67 in the EGA group and 85 in the NEGA group. Fifty-ve pairs were matched with similar background characteristics. After matching, the rates of successful conservative management were 89.1% (49/55) and 94.5% (52/55) in the matched EGA and NEGA groups, respectively (P=0.49). Although the median insertion days of ileus tube in the NEGA group were signi cantly lesser than those in the EGA group (7 [5-9] vs. 5 [4.5-7], P=0.017), other therapeutic outcomes did not differ signi cantly. In the NEGA group, 5.5%(3/55) achieved obstruction relief without gastrogra n administration. Aspiration pneumonia occurred in one patients of EGA group. Conclusions: Gastrogra n administration with ileus tube achieved a high rate of successful conservative management. Follow-up by decompression with ileus tube for at least 48 h after admission is required in patients with ASBO, which may avoid unnecessary gastrogra n administration and consequently reduce the total cost of treatment.