The teaching of Earth Sciences (ES) is particularly delicate and seems to be problematic for both learners and Moroccan teachers for multiple reasons. Based on this observation, this study aims at identifying the difficulties related to the teaching of ES by exploring the points of view of the Moroccan teachers toward this field. As an investigative tool, we used a questionnaire and semi-directive interviews with nearly 122 secondary school teachers of Life and Earth Sciences (LES). The results of our survey revealed that the major difficulties that hinder the teaching of natural sciences are mainly related to the teachers' university studies. Most of them had training in biology as well as in the relationship that the natural sciences maintain within time and space, the limited abstraction capacity of unmotivated learners, and the inadequacy of their prerequisites in these sciences. On the other hand, they were aware of the demotivating geological knowledge taught to the learners and the lack of initial and continuous training for teachers, especially for those who specialized in natural sciences.