Objective: To analyse the clinical characteristics of Mycoplasma pneumoniae pneumonia (MPP) in children under two years of age. Methods: A retrospective analysis was conducted on 112 paediatric cases of MPP admitted to our hospital between January 2022 and December 2023. Clinical data including symptoms, signs, imaging findings, and prognosis were collected. Results: Analysis of clinical symptom distribution revealed coughing in 100.0% of cases, comprising both paroxysmal dry cough and productive cough. Fever was present in 61.61% of cases, with additional manifestations including wheezing, vomiting, diarrhoea, and respiratory distress. Pulmonary rales were the most prevalent finding at 75.89%, alongside other signs such as diminished breath sounds. Imaging analysis of all 112 pneumonia cases revealed bronchopneumonia accounted for 70.54% of cases, representing a relatively high proportion. Treatment involved macrolide antibiotics, including azithromycin, with bronchodilators and corticosteroids added for significant wheezing. The overall treatment efficacy rate was 90.18%. Conclusion: Analysis of Mycoplasma pneumoniae characteristics in children under 2 years indicates that MPP in infants and young children under 2 presents with mild symptoms, pronounced signs, and relatively mild overall inflammation, resulting in a comparatively high overall cure rate.