Background and Goals: Spontaneous bacterial peritonitis (SBP) is a serious complication in patients with cirrhosis and ascites, with additional risks posed by multidrug-resistant organisms (MDRO). This real-world study evaluated clinical outcomes in patients with SBP and the impact of MDRO. Methods: This study identified US adults with SBP receiving guideline-recommended treatment with antibiotics and albumin from January 2012 to June 2022. Antibiotic utilization trends, health care resource utilization, and clinical outcomes [in-hospital and ICU mortality and hospital and ICU length of stay (LOS)] were assessed and stratified by MDRO status. Results: A total of 10,956 patients with 12,570 encounters were identified. Median age was 57.0 years (IQR=49.0 to 65.0), and 62.4% were male; suspected MDRO infections occurred in 15% of encounters. Third-generation cephalosporins were used in 71.6%, 49.2% had acute kidney injury, and 20.0% and 7.2% had hepatorenal syndrome and hepatic encephalopathy, respectively. Median hospital LOS was 7.2 days (IQR=4.3 to 12.9), with 17.7% in-hospital mortality. ICU care was required in 14.5% of encounters, with a median ICU LOS of 3.6 days (IQR=1.7 to 6.7) and ICU mortality of 29.7%. MDRO infections were associated with increased in-hospital mortality (OR=2.24, P <0.001) and decreased hazard of hospital discharge (ie, prolonged LOS; HR=0.43, P <0.001). Receiving albumin within 24 hours of admission was associated with a 72% higher hazard of hospital discharge (ie, shorter LOS; HR=1.72, P <0.001). Conclusion: This study highlights the clinical and resource burden of SBP, emphasizing the impact of MDRO infections and the importance of timely albumin administration concordant with clinical guidelines.