Since 2008, the year when Philosophy became a mandatory subject in Brazilian schools, researchers started focusing their studies in the teaching of that subject. Our research seeks to identify intrinsic and extrinsic factors that motivate high school students for the subject of Philosophy, in light of the Self-Determination Theory. To do so, we used a semi-structured interview and a questionnaire, which were applied in a public school and in a private school in Rio de Janeiro, with a sample of 12 students from the 1st and 3rd years of high school. The instruments asked students about their motivation to learn philosophy. The data obtained suggests a strong relationship between the learning of philosophy and intrinsic motivation. In addition, it confirms the importance of teachers motivational role in for the student learning. This work, having presented the conceptions of students about the concept and teaching of Philosophy, contributes to an understanding of the factors and contexts that generate motivation in students for learning philosophy, thus offering hints for the teaching of that subject and for thinking about school curriculum.