Background Although there is relatively much information about the status of cystic fibrosis disease in different countries of the world, limited data are available on this disease among Syrian children. Therefore, we did a retrospective study that included 173 children diagnosed with cystic fibrosis according to the diagnostic criteria. This study was conducted to determine the diagnostic, clinical, and genetic characteristics of patients with cystic fibrosis in Syria and to assess the relationship between the genotype and the phenotype of disease in these patients. Results As a result of the early classical manifestations, CF diagnosis was established in the present study by the age of 1 year in 78.6%; the mortality rate was 23.1% (82.5% of them were in the first year of life). The prevalence of respiratory and gastrointestinal symptoms was 81.5% and 78.6%, respectively with an average age of 7.8 and 3.4 months. Consanguinity was reported in 75.7% of the families. The most common pathogenic variant in the sample was F508del (36%) followed by W1282X (17%). There was a statistical correlation between incidence of steatorrhea and the presence of class I pathogenic variants. A relationship between the mortality rate and the presence of class II pathogenic variants (pathogenic deletion variants) was also observed. There was no statistical relationship between other clinical manifestation and pathogenic variant classes. However, the incidence of most CF-related conditions was a little higher in the presence of classes I, II, and III pathogenic variants compared to their incidence in the presence of classes IV and V pathogenic variants. Conclusions The number of cases diagnosed with cystic fibrosis in Syria is less than the number of real cases, and there is a need to perform CFTR gene sequencing on large sample sizes, to determine all CFTR pathogenic variants that could exist in Syrian patients and to make a better evaluation of the relationship between genotype and phenotype of the disease.