Background
 
Individuals with cystic fibrosis (CF) are at high risk of clinically significant anxiety, which can be related to lower treatment adherence and poorer health outcomes. So, it is associated with poor psychosocial and quality of life outcomes. The aim of this study was to assess the effectiveness of Viktor Frankl's Logo therapy on the mental health of pediatric patients with CF.
 
Materials and Methods: This research was a quasi-experimental based on pretest and posttest with a control group. The population under study includes pediatric patients with CF referring to Emam Khomeini hospital, Tehran, Iran, during 2018-19. The range of the participants’ age was between 12 and 16 years. The sample size was selected based on the convenience sampling method. The participants divided randomly into two groups: experimental, n=11 and control n=11. Participants in both experimental and control group completed questionnaires on The General Health Questionnaire (GHQ) before and after training. Treatment process for 45 minutes a week was applied among experimental group.  
 
Results: The mean and standard deviation of the patient's age in this study were 15.83± 0.87 years old. The results of this research showed that the score of mental health in the experimental group (25±6.8) increased after the intervention training (p <0.01), compared the control group.  
 
Conclusion
 
Based on the results of this study, the effectiveness of logo therapy in fostering mental health among pediatric cystic fibrosis patients with a mean age of 13-18 years was approved after nine sessions, 45 minutes once a week. According to the results, logo therapy helped children with cystic fibrosis improve their mental health.