Objective: Keeping symptom diaries on a regular basis may facilitate the execution of symptom-based action plans, enhance the patients' adherence to treatment program and finally allow better asthma control. We hypothesize that disease control in children who keep symptom diaries regularly would be better compared to children who do not keep symptom diaries regularly. Methods: Asthmatic children, aged between 6 and 17 years, who were monitored at least 2 years at our outpatient clinic and examined at least twice within the last year, were enrolled in this study. The patients were assigned to the following two groups: group I included the patients who keep symptom diaries regularly and group II included the patients who do not keep symptom diaries regularly. Asthma control parameters of patients during the last year were investigated. The number of asthma attacks require systemic corticosteroid use, the frequency of emergency department (ED) admissions and the number of attacks requiring hospitalization, forced expiratory volume in 1 s (FEV1) values and asthma control test (ACT) scores were compared. Results: 89 (26.2%) of 340 patients included in the study were identified to keep a symptom diary regularly. Although age (p = 0.20) and sex (p = 0.48) did not differ significantly between the groups, regular use of anti-inflammatory drug was found to be significantly higher in group I (p < 0.001). When all of the study parameters were compared using a multivariate analysis, the number of systemic corticosteroid use, ED visits, attacks requiring hospitalization and ACT scores and FEV1 did not differ significantly between the groups (p > 0.05 in all of the parameters). Conclusions: Keeping a symptom diary on a regular basis in asthmatic children was shown to have neither beneficial effect on the day-to-day asthma control nor a decrease in the future risk of asthma control.