This study aims to present the cognitive competences of the pre-service teacher about discovery learning approach in mathematical education. The study was conducted with 37 mathematics pre-service teachers who study Special Teaching Methods lesson in a state university in Turkey. Throughout the lesson, the approaches used in learning were examined with the pre-service teachers. Afterwards, some open-ended questions related to discovery learning approach were asked for the pre-service teachers to answer and they were expected to prepare an activity in which they would apply the approach and then evaluate it. After analyzing the retrieved data with qualitative research techniques, three main findings were achieved: The pre-service teachers have enough theoretical information on discovery learning approach and are able to meaningfully explain that information; their competences at preparing an activity in which they will apply discovery learning are quite low; most of them did not compare the discovery learning approach to other approaches.