Introduction: The incidence of pyogenic liver abscesses is estimated to be 3.6 per 100,000 in the United States. Achromobacter xylosoxidans (AX) is an aerobic, motile, gram-negative bacillus, often misidentified as Pseudomonas aeruginosa, that can be isolated in hospital and domestic sink drains. Bacteremia and bronchiolitis due to AX has been described in patients after liver transplantation for Caroli’s disease and cystic fibrosis, respectively. Although it may be found occasionally in the bile, it is very rarely the cause of liver abscess in immunocompetent patients. Rare cases of liver and intraabdominal abscesses caused by AX have been described in association with prior cholecystectomy. We describe a rare case of AX infection mimicking hepatic malignancy in an immunocompetent patient after cholecystectomy and ERCP. A 66-year-old female with history of open cholecystectomy for gangrenous cholecystitis, ERCP for gallstone pancreatitis, PPD+, and recent colonoscopy with polypectomy, was admitted for right upper quadrant abdominal pain, nausea, and weight loss. Laboratory work-up showed WBC count of 13 with 77% neutrophils, platelets 575, total bilirubin of 1.4 mg/dL, and alkaline phosphatase 255 U/L. CT of the abdomen revealed 2 solid masses in the liver. CEA, CA 19-9, AFP, and CA-125 were normal. CT of chest showed only emphysematous changes. Two needle liver biopsies showed fibroinflammatory tissue with focal necrotizing granulomas, and large droplet steatosis, compatible with an infectious process suggestive of AX. The patient was treated with sulfamethoxazole/trimethoprim 800/160 mg, and within 2 weeks, she demonstrated significant improvement in appetite and weight gain. After 6 weeks of therapy, she was asymptomatic with complete resolution of the lesions on repeat MRI. While AX is a ubiquitous waterborne nosocomial organism, it rarely causes infections in immunocompetent hosts. Hepatic involvement may mimic metastatic malignancy and may pose additional diagnostic challenges. It is important to be cognizant of this rare cause of liver abscess in immunocompromized and immunocompetent patients after cholecystectomy and ERCP.