The current study aimed to investigate the clinical, laboratory and radiological findings of the pneumonia cases in children that were confirmed as M.pneumoniae by polymerase chain reaction (PCR) testing and to reveal the factors that can be decisive in the diagnosis. Seventy-seven children were included in this study. The median age of the patients was 31 months (1 month-17 years 4 months). The 63.6% of the patients were younger than five years of age, 53.2% were girls and 46.8% were boys. During the eight-year research period, the frequency of M.pneumoniae in the patients hospitalized with the diagnosis of pneumonia was found to be 3.1%. The rate of M.pneumoniae as the underlying factor of pneumonia was found to be statistically significantly lower in patients aged 0-60 months compared to the patients aged 61-216 months. In patients with M.pneumoniae accompanied by viruses, the age group was more likely to between 0-60 months. The most common symptoms were cough (96.1%) and fever (74%). Physical examinations revealed that 70.1% of the patients had rales, 63.6% had tachypnea, 45.5% had oropharyngeal hyperaemia, 35.1% had subcostal-intercostal retraction, 31.2% had long expiration period, 26% had rhonchus, 24.7% had decrease in breath sounds, 15.6% had cervical lymphadenopathy, 13% had tachycardia, 3.9% had otitis media, 3.9% had tonsil hypertrophy and 2.6% had a maculopapular rash. The rate of hypoxemia was found to be 42.2%. When the physical examination findings of patients with only M.pneumoniae detected in multiplex PCR analysis and those with accompanying viruses in M.pneumoniae were compared, tachypnea, oropharyngeal hyperemia and decreased breath sounds were found to be statistically significantly higher in patients with M.pneumoniae only. Retraction was detected more frequently in patients with accompanying viruses. When the laboratory results of the patients were evaluated according to age, leukocytosis was detected in only 18.2% of the patients, while the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were found to be high in 75% and 85.7% of the patients, respectively. In the multiplex PCR analysis, the CRP values of the patients with only M.pneumoniae were found to be higher than the patients with accompanying viruses. M.pneumoniae was accompanied by viruses at the rate of 40.3%. The most common accompanying viruses were rhinovirus, adenovirus, bocavirus and metapneumovirus. The 55.8% of the patients had lobar-segmental consolidation, 46.8% had parahilar-peribronchial thickening, 18.2% had atelectasis, 11.7% had pleural effusion, 9.1% had increase in reticulonodular density, 6.5% had lymphadenopathy whereas no abnormality was observed in 5.2% of them. No diffuse interstitial involvement was recorded. The CRP value of the patients who had lobar segmental consolidation which was detected through chest X-rays were statistically higher than those without consolidation. In multiplex PCR analysis, the rate of parahilar-peribronchial thickening detected in chest X-ray findings was found to be higher in patients with M.pneumoniae accompanied by viruses compared to those with only M.pneumoniae. The rate of the patients who were given empirical antibiotics against atypical agents was 45.5%. The rate of empirically administered antibiotic treatment for atypical agents after being hospitalization was higher in patients diagnosed with only M.pneumoniae compared to patients with M.pneumoniae and viruses. One patient (1.3%) died. As there are no typical clinical, laboratory or radiological findings specific to M.pneumoniae pneumonia, all of the findings should be assessed as a whole to establish a diagnosis. Besides, for the detection of M.pneumoniae, diagnostic tests which are cost effective, with rapid results and are capable of distinguishing colonisation from active infection should be developed.