Problem solving, being one of the important skills in mathematics course, is seen as a vital aspect in terms of academic achievement as well as lifelong success of students. In addition to this, a set of problems and difficulties are experienced in solving mathematical problems. To the aim of solving the experienced problems and difficulties it is considered that identification of students' perceptions would provide ease. In this context it is stated that determining the metaphors students generate towards the concept of "mathematical problem" could be indicative. Based on this necessity the objective of present research is to designate the metaphors of secondary school students towards the concept of "mathematical problem". In this research one of the qualitative research patterns, phenomenological pattern, has been used. Participants of the research are composed of sixth, seventh and eighth grade students studying in two different secondary schools in 2011 - 2012 academic year. In the process of data collection each student was asked to complete the expression in the way they liked: "In my opinion, mathematical problem is like. because." The analysis and interpretation of students' metaphors was conducted according to the process formed by Saban (2008). In the research 114 metaphors collected from 161 students were gathered under seven conceptual categories.