Context: Upper gastrointestinal endoscopy is a critical diagnostic technique for gastrointestinal disorders. Therefore, proper child preparation is highly recommended to maintain the examination more acquainted more comfortable. Aim: Evaluating the calming techniques effect on health parameters of children undergoing upper gastrointestinal endoscopy and their mothers' satisfaction. Research design: The present study employed a quasi-experimental research design. Setting: This study was accomplished at the endoscopy unit at Benha University Hospital in Benha City. Study sample: A purposive sample of 106 children and their mothers. Tools: Five tools were adopted for data collection, I: Structured interview questionnaire sheet; II: Child Behavior Checklist; III: State Anxiety Scale; IV: Children Fear Scale; V: Mothers' Satisfaction Questionnaire. Results:  After the calming technique intervention, it was observed that mild anxiety was prevalent among most children in the study group, in contrast to the control group where the majority of children in control group experienced severe anxiety immediately after calming technique intervention. Moreover, significant statistical differences were observed between the study group and the control concerning physiological parameters. Additionally, over three-quarters of mothers in the study group had an improved satisfaction level concerning upper gastrointestinal endoscopy one hour after upper endoscopy. Conclusion: This study could be concluded that calming techniques were effective in improving health parameters among children undergoing upper endoscopy in the study group compared to the control group. Also, mothers of children in the study group who received calming techniques, experienced high satisfaction level. Recommendation: Conducting educational programs periodically for nurses in the endoscopy unit concerning the different calming techniques methods that can be applied for children before upper endoscopy.