The study aims to investigate the inclusion of environmental education concepts in Islamic studies textbooks at cycle two-Basic education and students learning of these concepts. The method adapted by the researcher is through the answering the following questions: To what extent do environmental education concepts exists in Islamic studies textbooks at cycle two of Basic Education? What learning levels attained by students for these concepts by the end of cycle two of Basic Education? Is there any gender variation with regard to learning of environmental education concepts in Islamic studies books? In order to answer the above questions, the researcher adopted two tools: the first one is a tool to analyze the content, consisting of a list of educational concepts; the second is test on the environmental concepts included in Islamic studies books for cycle two of Basic education. The validity and stability of the tools were verified. The study sample contains in its first part all Islamic studies textbooks used for cycle two-Basic Education (grade 5 - 10 ) during the academic year 2008/2009. The second part of the sample consists of 400 students (Male & Female) representing 2.5 % of the different levels. The study adapted the analytic description method. The researcher used statistical methods to answer the questions represented by mathematical means, standard diversions, percentages and (T) test. The most important results reached by study are as follows: The number of terms dealing with environmental education concepts in Islamic studies books at cycle two-Basic education was (557) out of original (1612) concepts contained in the books for their level, representing a percentage of 34.5%. Environmental ethics concepts were largely represented (53%) while (Environmental problems) concepts were least represented (3%). The response of the targeted study sample to the test on environmental concepts was 57.97% of the total mark of the test. This is less than the acceptable educational level (60%). These were difference of statistical significance at the level (a = 0.05) with regard to the learning achievements of the environmental concepts contained in Islamic studies books for cycle Two-Basic Education in the Sultanate of Oman. This can be attributed to gender variation and for the benefit of female students. On the light of the results, the researcher made several recommendations including the use of the list on environmental Educational concepts reached by the preset study during the planning phase to include and integrate in the curricula of basic education with a need to establish a balance in the major environmental concepts especially those related to environmental problems.