329 ©2019 The author and IJLTER.ORG. All rights reserved. International Journal of Learning, Teaching and Educational Research Vol. 18, No. 11, pp. 329-347, November 2019 https://doi.org/10.26803/ijlter.18.11.20 Teachers’ Beliefs about the Nature, Teaching and Learning of Mathematics and Sources of these Beliefs Mohammad Alkhateeb Hashemite University Zarqa, Jordan Abstract. This study aimed at investigating the beliefs of mathematics teachers and the relationship of these beliefs with their teaching practices, and the acquisition sources of these beliefs. The study population comprised (100) male and female teachers who were selected randomly out of those who teach the 12th graders. The study applied quantitative and qualitative methods together. The data were collected through the beliefs questionnaire, note card and interview card. The results showed that the teachers had a blend of swaying beliefs between constructivism and behaviourism about the nature of mathematics and math teaching. There was a lack of compatibility between the teachers' beliefs and their teaching practices. The results further showed that the primary sources of mathematics teachers' acquisition of their beliefs were: the social surrounding, former teachers, university studies, technology, media, self-reflection, personal experience, professional colleagueship, scientist, religious orientations, educational supervisors, examinations system and school principals. Keywords: Teachers’ beliefs; Nature of mathematics; School mathematics; Belief systems; Teaching practices. 1. Introduction Preparing the teachers for the twenty-first century is not limited to developing their knowledge and skills required for their industrial assignments. Instead, the integrative understanding between teacher preparation and training requires, at first, calls for focusing on the development of his views about the entire components of the educational process. At that point, the study of the teachers' beliefs emerges as one of the underlying mechanisms to achieve these objectives. Studies of (Beswick, 2012; Charalambous & Philippou, 2019; Cross, 2015; Jong & Hodges, 2013; Minarni et al, 2018) indicated that the teaching practices of mathematics teachers are related to his beliefs. Cross (2015) defined the beliefs, generally, as many thoughts and conscious and unconscious perceptions about