In the Western intellectual tradition, René Descartes and Edmund Husserl are two prominent philosophers who seek to establish philosophy in a similar way. Descartes' grammatical doubt and Husserl's epoche are two fundamental starting points for the establishment of philosophy. Descartes' grammatical doubt is his initial step to find the "I". Husserl's epoche is also a path to reach the "transcendental I". These two methods and their final results, while apparently similar, have fundamental differences. Descartes' grammatical doubt is a method to reach absolute certainty. He seeks to build a solid foundation for knowledge by doubting all beliefs. In contrast, Husserl's epoche is a "suspension" or "bracketing" to reach a transcendental subject and the field of phenomenological research. Both methods, despite their fundamental differences, have had a tremendous impact on contemporary philosophy and have served as powerful tools in the critique of epistemology and the foundation of new sciences. In the following work, a more precise reading of Descartes's order of doubt will be presented, and we will further clarify the distinction between them by examining Husserl's epoche and through his criticisms of Descartes.