The objective of this research is to analyze the sport activities carried out in the natural environment represented in the textbooks of Physical Education (PE) in Primary Education (EP), published according to Organic Law of Education 2/2006, of May 3rd, (LOE). 4339 images have been analyzed, from 44 different textbooks, belonging to eight Spanish publishers. The SAIMEF (Physical Analysis Images Analysis System) tool, elaborated ad hoc, was used to analyze the content of the images. The pilot test, panel of experts and triangulation with several observers were some of the scientific criteria that endorsed this tool. The results show that the presence of images related to sport activities in the natural environment continues to be very scarce in PE textbooks. The editorial Teide represents in greater proportion this type of activities compared to the rest of publishers. In the third cycle appears a greater number of images, predominating drawings over pictures. The most represented sport activity is the orientation, with a 25.6%, included within the multidisciplinary sports, prevailing the terrestrial environment. The representation of sports in the natural environment varies according to the analyzed publishers. Thus, in Anaya and Bruño predominates the orientation, in Edelvives, Paidotribo and Serbal predominates the ski, and in the publishers Santillana and Teide prevails the escalation. It is necessary to reflect on the low representation of these activities in EF textbooks.