The study aims to identify the extent of including the controversial issues in the social studies books for grades (11-12), in Post Basic at the Sultanate of Oman. In order to answer the study's questions, the researcher prepared a list of controversial issues that supposed to be in the content of these textbooks. The list has been derived from the literature and previous studies on the controversial issues. It was presented to a group of specialists in order to express their opinion till the final image of the list was reached. It contains (41) of the controversial issues which were divided into the five areas: political controversial issues, economic controversial issues, environmental controversial issues, social controversial issues, and cultural controversial issues. Then, the content of the social studies textbooks for grades (11-12) post basic was analyzed according to the list. The idea, in both explicit and implicit was used as a unit of analysis of the content, along with the aids of illustrations, such as texts, maps, tables, activities, images, questions, and figures. Also, stability has been verified in a manner of consistency between the researcher's analysis and another analyst, and the percentage of stability was (92%). The most important study's results were as follows: 1- A list of the controversial issues that the social studies textbooks are supposed to include for grades (11.12). 2- The percentage of controversial issues was varied in the five areas of the social studies textbooks. The political controversial issues was the first on the list with (32.95%). Second, the cultural controversial issues was with (30.55%). Third, the environmental controversial issues was with (16.8%). Fourth, the economic controversial issues was with (11.63%). Finally, the social controversial issues was with (8.07%). 3- Areas of controversial issues were equally distributed in the social studies books for grades (11612). Grade 12 was on the first place with (61.96%). Then, grade 11 with (38.04%). The researcher recommended the need to include the controversial issues of the various fields in the post basic education social studies textbooks ; because of their impact on the development of thinking skills, and the balance of presenting the controversial issues between grades 11 and 12. She also presented a set of proposals for future studies.