The study presents the philosophy of law and state of the most eminent thinkers of German idealism: Kant, Fichte, Hegel. The analysis focuses on the following issues: the idea of law, the idea of state and the grounds of international legal order. The main aim is to show the importance of German idealistic philosophy to present-day legal thinking, especially to philosophy of international law. In the author's estimation, German idealistic philosophy can be availed itself as an explanation of the divided ongoing debate into positivism and naturalism, political competition and common values, pluralism of the society of states and hegemony of great powers. The following conclusions can be drawn from the critical analysis of German idealistic thought: 1) legal orders of states are of great weight for international legal order considering their strong mutual relations; 2) overestimation of the will of state denies sovereignty of other states; 3) legal consciousness (opinio iuris) of common values important for all states and their nations establishes the basis of a just international legal order, that is to say an order which can protect both states and individuals. Taking into account the above statements, current international practice, on the one hand, speaks in favour of Kant's thought and on the other against Fichte's and Hegel's ones. For Kant's recognition of peace as the most important value within interpersonal and international relations leads him to the conception of 'civitas gentium', that is the legal shape of the society of states. Fichte and Hegel, however, treat state as the biggest value. Consequently, interstate relations create a source of wars just as Hobbes's state of nature. That is why their theories cannot account for objective importance of international law. No wonder that Fichte's and Hegel's theories reject Kant's idea of perpetual peace and present international law as an external state law depending on its arbitrary will.