Introduction: Critically ill children admitted to the pediatric intensive care unit are in a vulnerable position at the time of hospitalization. Healthcare workers play an important role in care of these children. Because of many painful interventions, they must have a great deal of practical, theoretical and specific knowledge of pain and of identifying and alleviating pain. Admission of a child to the intensive care unit presents a difficult situation not only for the child but also for the parents or caregivers. In order to establish a positive relationship between parents, child and healthcare worker, the concept of family-centred care is used throughout hospitals. Purpose: The purpose of the thesis was to describe the pain of a critically ill child. The goals of the diploma thesis are: to find out which painful interventions are most often implemented and which pain assessment scales for critically ill children are most commonly used and to describe the role of parents in the relief of pain. Methods of work: A descriptive method of work with a review of scientific and professional literature was used to prepare the diploma thesis. Domestic and foreign literature was searched from December 2018 to July 2019 in the MEDLINE, Cochrane, Science Direct and Google Scholar databases. The literature from 2008 to 2019 is used. Results: Painful and stressful interventions are inevitable in the pediatric intensive care unit. The number and type of painful interventions performed on a daily basis in such a unit depend on the individual's medical condition. Studies show that a critically ill child experiences at least seven painful and three stressful interventions a day. Multidimensional scales which assess physiological and behavioural indicators are used to evaluate pain in the pediatric intensive care unit. Parents describe their engaging in painful interventions as important and beneficial for them and their child. Discussion and conclusion: A critically ill child is sensitive and susceptible to painful stimuli. Because pain stimulus is a sensory and emotional experience, critically ill children show it on multiple levels. Conditions for successful recognition and alleviation of pain are good knowledge of healthcare workers, observation of the child, assessment of pain by using scales, quick responses and pain relief with various methods and parental involvement.