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Objective: To delineate the pathogen spectrum and epidemiological features of acute respiratory infections (ARI) among pediatric patients in Beijing during 2024-2025. Methods: In this cross-sectional study, 1 435 children diagnosed with ARI were enrolled from outpatient, emergency, respiratory medicine, and critical care medicine department of Capital Center for Children's Health, Capital Medical University between July 2024 and June 2025. Respiratory specimens were collected and screened for 28 respiratory pathogens using multiplex real-time quantitative PCR. Specimens positive for influenza virus, respiratory syncytial virus (RSV), human metapneumovirus (HMPV), and human rhinovirus were further subtyped. Patients were categorized into influenza-like illness (ILI) and severe acute respiratory infection (SARI) groups. Positivity rates across different sources, visit periods, and age groups were compared using the chi-square test and Wilcoxon rank-sum test. Results: Among the 1 435 children, there were 770 males and 665 females, with an age at presentation was 6.7 (4.4, 12.6) years. The total positive rate for the 28 pathogens was 80.5% (1 155/1 435). The ILI group comprised 1 040 cases (549 males, 491 females) with age at presentation was 6.8 (4.5, 12.8) years and the positive rate of 76.6% (797/1 040). Common viral pathogens included human rhinovirus 15.7% (163/1 040), human parainfluenza-virus (HPIV) 10.3% (107/1 040), and Influenza virus 7.1% (74/1 040), while common bacterial and atypical pathogens included Mycoplasma pneumoniae (MP) 18.7% (194/1 040), Haemophilus influenzae (HI) 18.4% (191/1 040), and Streptococcus pneumonia (SP) 17.1% (178/1 040). The SARI group comprised 395 cases (221 males, 174 females) with age at presentation was 6.5 (4.0, 12.3) years and the positive rate of 90.6% (358/395). Common viral pathogens included human rhinovirus 17.2% (68/395), RSV 9.9% (39/395), and HPIV 7.1% (28/395), while common bacterial and atypical pathogens included MP 51.4% (203/395), SP 15.4% (61/395), and HI 13.4% (53/395). Co-detections of multiple pathogens accounted for 43.0% (497/1 155) of all positive cases. The positivity rates of RSV and MP in the SARI group were significantly higher than those in the ILI group (both P<0.001). RSV positive rate was the highest in children under 1 year of age, accounting for 15.3% (13/85), while MP positive rate was the highest in children aged 7 to 18 years, accounting for 38.1% (205/538). Typing results revealed that 96.5% (83/86) were typed to H1N1 among influenza virus A cases, while 58.3% (42/72) were genotyped as RSV-A ON1 among RSV cases, 86.3% (63/73) were subtyped to B2 among HMPV cases, and 45.0% (104/231) were typed to human rhinovirus-A among human rhinovirus cases. Conclusion: The pathogen spectrum of pediatric patients with ARI in Beijing from 2024 to 2025 was characterized by the alternation or co-circulation of multiple bacteria and viruses, a high rate of co-detection of multiple pathogens, and different between SARI and ILI groups. Influenza virus was dominated by H1N1, RSV by RSV-A, HMPV by HMPV-B2, and human rhinovirus by human rhinovirus-A.