This study was designed according to the mixed research method in which quantitative and qualitative research methods were used in order to identify the challenges confronted by classroom teacher candidates in solving mathematical problems and the factors affecting how they choose these representations. The population of this study consisted of 100 3rd year students attending the primary teaching department of Cukurova University during the 2012-2013 academic year. In identifying the samples, the criterion sampling method, a purposeful sampling method, was used. The data collection tools consisted of The Use of Multiple-Representations in Problem Solving Test and a semi-structured interview form prepared by the researcher. At the end of the research it was discovered that classroom teacher candidates could use different types of multiple representations in solving mathematical problems. However, they used spoken language and algebraic representations the most. During the interviews, teacher candidates emphasized that experience and the content of the problem are the most important factors in identifying which multiple representations to use. Another important result obtained from the research is that teacher candidates can have problems forming a suitable theme for problems and shifting between representations. For this situation, it can be suggested that giving importance to the concept of multiple representations in the teaching of mathematics as well as doing in-class application studies intended to solve and associate problems using the concept of multiple representations would be beneficial. In that way, teacher candidates can guide their students towards different points of view while solving problems.