Objective To investigate the clinical characteristics of patients with pyogenic liver abscess (PLA) under different immune status, and analyze the influencing factors for poor prognosis. Methods Clinical data of 104 patients with PLA admitted to Meng Chao Hepatobiliary Hospital of Fujian Medical University from November 2017 to November 2021 were analyzed retrospectively. Patients were divided into immunocompromised group and immunocompetent group based on their basic immune status, and compared in the aspects of general conditions, laboratory and imaging results, complications, treatment plans as well as disease outcomes. According to the treatment results, 104 PLA patients were divided into good prognosis group and poor prognosis group. Risk factors for poor prognosis were analyzed with multivariate logistic regression. Results A total of 104 patients were recruited, including 70 immunocompetent patients and 34 immunocompromised patients. Serum procalcitonin level, detection rate of Klebsiella pneumoniae, and length of hospital stay of patients in immunocompromised group were higher than those in immunocompetent group. Serum albumin level was lower than that in immunocompetent group (all P < 0.05). The top two pathogens detected in both groups were Klebsiella pneumoniae and Escherichia coli. Poor prognosis rates (ineffective treatment, including death) in immunocompromised group and immunocompetent group were 26.5% and 7.1% respectively, with statistically significant difference (P < 0.05). There was no significant difference in clinical manifestations, complications, treatment plans, in-hospital case fatality rates and other indicators between two groups (P>0.05). Multivariate logistic regression analysis showed that combination of immunosuppressive underlying disease (OR=8.041, P=0.008), abscess diameter≥10 cm (OR=12.896, P=0.005), septic shock (OR=7.714, P=0.041) were independent risk factors for poor prognosis of PLA patients. Conclusion When PLA patients is combined with underlying diseases of low immunity, infection is more severe, and the nutritional status is worse, indicating longer length of hospital stay and poor prognosis. For immunocompromised PLA patients, more active treatment strategies and focused monitoring are required.