Background: Portal venous gas (PVG) is a rare finding and has a grave prognosis. The most common and critical underlying pathology of PVG is bowel necrosis. However, bowel necrosis is sometimes difficult to accurately diagnose. We retrospectively analyzed data from patients that contributed to the decision to perform emergency surgery and bowel resection. Methods: Between 2009 and 2019, 25 consecutive adult patients with PVG were identified retrospectively and divided into the Operation and Non-operation groups. The Operation group was further subdivided into the Bowel resection and Non-resection groups. Clinical, laboratory, and radiographic variables were analyzed. Results: Conservative management was successful for 32% (8/25) of patients (Non-operation group: mortality 0%); 68% (17/25) were treated surgically (Operation group: mortality 35.3%). In the Operation group, 52.9% (9/17) underwent bowel resection (Bowel resection group: mortality 55.6%); however, bowel resection was unnecessary in 47.1% (8/17) of cases (Non-resection group: mortality 12.5%). Univariate analysis revealed significant differences between the Operation and Non-operation groups in GCS, APACHE II, abdominal distention, CRP, lactate, and CT findings of bowel dilatation, pneumatosis intestinalis, and attenuation of contrast effects of the bowel wall. However, with the exception of GCS, there was no significant difference between the Bowel resection and Non-resection groups. Conclusions: Analysis of clinical, laboratory, and radiographic variables can inform decisions on conservative management. However, 47.1% of the present patients who underwent surgery for suspected bowel necrosis did not require bowel resection, suggesting that this approach alone may not be sufficient to avoid non-therapeutic laparotomy. A new approach should be developed to improve this situation.