Understanding students’ mathematical thinking in problem solving process plays an important role in facilitating the solution. Hence, teachers or pre-service teachers need to understand students’ thoughts and guide them to the correct answer. The aim of this study was to examine pre-service teachers’ approaches to guiding students in problem solving process. Designed as a case study, this study was carried out with five pre-service primary mathematics teachers. In the study, participants’ dialogues with 7th grade students were examined through 3 non-routine problems. The dialogues were transcribed and it was tried to reveal what kind of approaches the participants displayed. The content analysis was used in data analysis. The findings revealed that pre-service teachers followed Polya's problem-solving steps during their guiding approaches. Most pre-service teachers provided appropriate guidance in understanding the problem, selecting and implementing appropriate strategies for the problem; however, they failed to use the evaluative approaches sufficiently.