Abstract: OBJECTIVE To investigate the epidemiological and clinical characteristics of Pneumocystis jirovecii pneumonia (PJP) in children from a hospital in Shandong Province, providing a basis for early identification and precise diagnosis and treatment of pediatric PJP. METHODS A retrospective collection and analysis was conducted on 66 non-HIV-infected children diagnosed with PJP at Qilu Hospital of Shandong University from May 2021 to May 2025. Epidemiological features were analyzed, and clinical characteristics were compared among different infection statuses and underlying disease groups. RESULTS The median age of PJP children was 1 year and 10 months, with infants (≤3 years), especially those under 1 year, accounting for the highest proportion. Spring (39.39%) was the peak incidence season. Mixed infections were present in 87.88% of cases, primarily involving human herpesvirus (30.30%) and Mycoplasma pneumoniae (19.70%). The mixed infection group exhibited higher rates of cough (70.69% vs. 25.00%, P=0.032) and oxygen therapy requirement (94.83% vs. 62.50%, P=0.020), while the single-infection group had higher lactate dehydrogenase (LDH) levels (580 U/L vs. 385 U/L, P=0.012). Underlying diseases were present in 48.48% of children. The hematological disease group showed higher rates of mechanical ventilation (40%), transfusion (33.33%) and immunosuppression than those of the no underlying disease group (all P＜0.05). The immune system disease group had the longest hospital stay (39.44±42.51 days). The mortality rate of children with PJP was 6.1%. CONCLUSIONS Pediatric PJP predominantly affects infants and young children, with a high incidence in spring and frequent mixed infections. Children with hematological diseases are more prone to severe progression. Clinical management should adopt stratified approaches based on underlying disease and pathogen spectrum.