This study aimed to analyze the Genre-based Approach (GBA) and Differentiated-Instruction (DI) reflected in the writing learning activities of a Kurikulum Merdeka textbook "Work in Progress" for grade 10 senior high school by using deductive or directed qualitative content analysis (DQICA) method. There have been several studies in investigating GBA in Indonesia textbooks, however the study of GBA in the newly produced Kurikulum Merdeka textbook is still limited. Unlike GBA, the study of DI in a textbook is still under researched. Thus, this study attempted to explore GBA and DI reflected in the newly produced Kurikulum Merdeka textbook. In relation with GBA, the findings suggested that a suitable GBA structure, a flexible TLC GBA implementation and GBA stages activities are found in the textbook. However, some issues in the implementation of GBA are still found in the textbook. In relation with DI, some elements of DI are also reflected in the textbook. Considering the conclusion, several suggestions are made based on the reflections of GBA and DI in the textbook.