Abstract: The Munich Pact is a product of the Appeasement Policy, which seemingly functions to maintain regional peace of England and France but in nature is a product of imbalanced social statuses and nation strengths. It reveals such kind of power relation that the more powerful countries (England, France, Germany and Italy) control or even suppress the less powerful country (Czechoslovakia). From the Systemic Functional Perspective, the theory of three Meta functions is utilized, attempting to analyze how The Munich Pact reflects such unbalanced power relation on the level of lexico grammar. To be specific, ideationally, the process types and voice of the discourse are analyzed. Interpersonally, speech function of modality and mood metaphor are analyzed. Textually, theme type is analyzed. Language and power are closely related. Language is perhaps the primary medium of social power. Language is power, which functions as a tool for some people to dominate others. By analyzing the language of a certain discourse, especially a forensic discourse, the power relations of the participants can be effectually revealed through the language characteristics. Thus by analyzing language of The Munich Pact, power relations of the four countries (England, France, Germany and Italy) and Czechoslovakia can be profoundly revealed. It is believed that analysis based on Systemic Functional Linguistics offers an effective way to analyze the hidden social relations and ideology of The Munich Pact.