In ideal circumstances, parents are the most devoted advocates for their children.They have first-hand information about their children and care passionately about their welfare. Therefore, the law recognizes parents as guardians of children's welfare and gives them substantial autonomy in making the decision for their children. Sometimes the actions of well-meaning parents, as in the case of the immediate medical intervention, could be a subject of testing limits of parental autonomy. It is especially noticeable when parental decisions represent a risk for child well-being, and the state has to intervene in order to protect it. However, the decision whether the state intervention into the parent-child relationship is legitimate is quite difficult since it is necessary to take into account a specific legal character of the parent-child relationship and balance between the parental autonomy and the best interest of the child. With an aim to evaluate the legitimacy of limiting parental autonomy in case of immediate medical intervention, the author will analyse the extent to which parental autonomy should be free of coercive intrusion of the state.Keywords: parental autonomy, the best interest of the child, harm standard, fiduciary character of the parent-child relationship SWS INTERNATIONAL SOCIETY SWS Journal of Social Sciences and Art -47 -