Abstract Background To evaluate comparative outcomes of outpatient versus inpatient treatment and antibiotics versus no antibiotics approach in the treatment of uncomplicated (Hinchey 1a) acute diverticulitis. The protocol of this review was registered in PROSPERO (CRD42023488826). Methods A systematic online search was conducted using electronic databases. Comparative studies of outpatient (OP) versus inpatient (IP) treatment and antibiotics (ABX) versus no antibiotics (NABX) approach in the treatment of uncomplicated (Hinchey 1a) acute diverticulitis were included. The primary outcome was diverticulitis recurrence. Emergency surgical resection, elective surgical resection, development of complicated diverticulitis, mortality rate, and length of hospital (LOS) were the other evaluated secondary outcomes. Results The literature search identified 14 studies (n=3,875) comparing NABX (n=2,008) versus ABX (n=1,867). The NABX group showed a lower disease recurrence rate and shorter LOS compared with the ABX group (P=0.01) and (P=0.004). No significant difference was observed in emergency resections (P=0.33), elective resections (P=0.73), development of complicated diverticulitis (P=0.65), hospital re-admissions (P=0.65) and 30-day mortality rate (P=0.91). Twelve studies (n=2,286) compared OP (n=1,021) versus IP (n=1,265) management of uncomplicated acute diverticulitis. The two groups were comparable for the following outcomes: treatment failure (P=0.10), emergency surgical resection (P=0.40), elective resection (P=0.30), diverticulitis recurrence (P=0.22), and mortality (P=0.61). Conclusion Compared with the use of ABX, the NABX approach seems to provide similar clinical outcomes and shorter LOS. Moreover, OP treatment of Hinchey 1a acute diverticulitis is comparable with IP management and presumably leads to cost savings in depleted healthcare systems