Abstract: In the Introduction to critique of Hegel's philosophy of law (Introduction for short). Marx exposes and criticizes "religion" and "speculative philosophy" as targets. Although there are no "ideology" terms, Introduction contains the basic principle of Marxist ideology: the inverted world produces the inverted world consciousness; practice is the most thorough revolutionary form; theoretical liberation is of special practical significance; it is urgent to expose the domination of capital over individuals. These basic principles of ideology show that Marx's ideology in this period has reached a historical height.