Objective Identification of the nurses and fathers' understanding of the stress sources facilitates nursing interventions and increases parental satisfaction. Materials and methods The quasi experimental study with pretest and posttest was administered to a sample size of 70 fathers with preterm neonates hospitalized in the NICUs of Gorgan University of Medical Sciences in 6 months. The Parental Stressor Scale (PSS) was used. The data were analyzed using descriptive and analytical statistical methods. Results Evaluation of the differences in the domains showed that narrative writing had significant effects on all three domains. The results showed that the highest stress reduction was observed in parents' relationship followed by infant behavior and appearance while the lowest stress reduction was observed in the sights and sounds in the intervention group. Conclusion Narrative writing may be considered an efficient supportive intervention to reduce the fathers' stress, infant behavior and appearance in the NICUs.