The purpose of the study was to examine primary pre-service teachers' difficulties of the teaching of mathematics with micro-teaching method. The participants of the study were 15 third grade pre-service teachers from the department of primary education in the faculty of education. In this grade which includes four sections, there were approximately 150 pre-service teachers. All of them taught mathematics with the micro-teaching method in a period of 40 minutes. To gather data, a semi-structured interview was administered. Later the recorded interviews were transferred to written texts and analysed. The pre-service teachers' responses were qualitatively analysed to characterize patterns and categorize answers. The main results of the study revealed that before the teaching the pre-service teachers were concerned about classroom management, excitement, lack of materials, unable to use time effectively. A majority of them indicated that, during their teaching, they were most forced into managing classroom and encouraging students' class participation. The artificial nature of micro-teaching negatively influenced pre-service teachers' classroom management and prevented to implement their teaching plans as they wished.