The purpose of this research is to determine the impact of augmented reality technology and geometry teaching on elementary school mathematics teacher candidates' technology acceptance and to examine participants' views on augmented reality. The sample of the research was composed of 40 elementary school mathematics teacher candidates who were freshman students in the faculty of education of a university which located in the central Anatolian region of Turkey during the fall semester of 2016-2017 academic year. Participants in the study were given a training seminar on teaching geometry via augmented reality (AR). They were provided with the opportunity to develop teaching materials for AR. At the end of this process, their opinions on the use of these materials were taken. Both qualitative and quantitative research methods were used in the research. The quantitative data of this study were collected by the Technology Acceptance and Use Scale for Information and Communication Technologies and the qualitative data were collected through semi-structured interviews. The themes and codes related to the usefulness of geometry teaching supported by augmented reality teaching emerged by means of qualitative content analysis. The t-Test, one of the parametric tests, was used to analyze the quantitative data. The data obtained from the semi-structured interview forms were classified under 9 categories and 35 themes. As a result of data analyses, it was found that the teacher candidates' attitudes towards the effectiveness geometry instruction supported by the augmented reality technology were positive but as regards' teacher candidates' intentions to use augmented reality technology, it was observed that some of them had reservations because of technological limitations, such as recognition of signs and freezing of the augmented reality environments. Keywords: augmented reality (AR), geometry teaching, mathematics teacher candidate, technology acceptance and use