Objective: To analyze serum interleukin-6 (IL-6), procalcitonin (PCT) and C-reactive protein (CRP) to identify the significance of bacterial and viral respiratory infections (RTI) in children. Methods: 100 children with bacterial and viral RTI admitted to our hospital were selected as the disease group, and the cases were collected from January 2023 to December 2024, which were classified into 42 cases of bacterial RTI and 58 cases of viral RTI according to the type of infection, and 100 children with the same period of health checkup in our hospital were selected as the health group. All of them were tested for IL-6, PCT, CRP levels, and IL-6, PCT, CRP levels were compared between the disease group and the healthy group, and between the children with bacterial RTI and viral RTI, and the positive rates of IL-6, PCT, CRP alone and in combination were counted for the detection of bacterial and viral RTI. Results: Compared with the healthy group, the levels of IL-6, PCT and CRP in the disease group were higher (P < 0.05). Compared with viral RTI, the levels of IL-6, PCT and CRP in children with bacterial RTI were higher (P < 0.05). The positive rate of bacterial RTI detected by the combined detection of the three was 92.86%, which was higher than that of IL-6 detection at 69.05%, PCT detection at 59.52%, and CRP detection at 71.43% (P < 0.05). The positive rate of the combined detection of viral RTI by the three was 94.83%, which was higher than that by IL-6 detection (79.31%), PCT detection (58.62%), and CRP detection (75.86%) (P < 0.05).. Conclusion: The expression levels of serum IL-6, PCT and CRP in bacterial and viral RTI in children are relatively high. The combination of the three can increase the positive detection rate of RTI.