Objectives: Our research aimed to study the microbiology and antimicrobial resistance in asymptomatic bacteriuria (ASB) among Omani pregnant women. Methods: We conducted a retrospective study that included data from 196 Omani pregnant women with ASB who received care at Sultan Qaboos University Hospital from 2010–2019. Data were obtained from the patients’ electronic medical records including demographics, clinical details, isolated organisms, antimicrobial susceptibility results, and prescribed antibiotics. Results: ASB was detected in 56.1% of cases during the third trimester. Klebsiella pneumoniae (32.1%) was the most frequently isolated organism, followed by Escherichia coli (29.6%). Twenty-one (10.7%) isolates were extended-spectrum betalactamase (ESBL)-producing organisms. The overall microbiological susceptibility pattern showed that organisms have a high susceptibility rate to nitrofurantoin reaching 82.8%, followed to a lesser extent by cefuroxime and augmentin. The susceptibility of E. coli and K. pneumoniae to cefuroxime was 74.1% and 71.4%, respectively. Only 52.4% of all isolated ESBL-producing organisms were susceptible to nitrofurantoin. Conclusions: K. pneumoniae and E. coli were the most frequently isolated bacteria in ASB, representing 60.7% of total isolates. A high prevalence of ESBL-producing organisms, 10.7% of the total isolates, was observed. Cefuroxime is an appropriate empirical antibacterial therapy for ASB and urinary tract infection in pregnant women. Nitrofurantoin should be considered for empirical antibiotic therapy in settings of high prevalence of ESBLproducing organisms.