The Author presented an analysis of the procedures and alternatives to the detention of migrating and refugee children in the Polish legal system, significantly influenced by European Union law. The Author pointed out legal solutions within the Polish legal system entangled with international law. It was emphasized that the continued use of child detention contradicts commitments made in international and regional legal instruments aimed at eliminating this practice. Detaining children can have serious negative consequences for their physical and mental health; therefore, alternatives to detention should be considered. Attention was drawn to the necessity of interpreting and applying Polish law in accordance with international human rights standards, including the principle of the best interests of the child to ensure the safety and protection of minor migrants and refugees.