This study aimed to investigate the changes in teacher perceptions regarding the use of technology subsequent to the training about technology integration in mathematics teaching. A training program that included combined technology, pedagogy and content knowledge was prepared and implemented on pre-service teachers with this aim. Exploratory sequential mixed method, one of the mixed method designs that include qualitative and quantitative research techniques, was utilized in the study. While pretest-posttest experimental design with no control groups was used in the quantitative dimension of research, pre-service teachers' written views were collected during the qualitative part of the study. Study participants were 34 pre-service teachers attending Middle School Mathematics Teaching Department of a state university during the spring semester of 2013-2014 academic year. Perception Scale for Technology Use and interview forms were used as data collection tools. Descriptive statistical methods and t-test were utilized for analyzing quantitative data whereas content analysis was preferred for qualitative data. Research results presented that significant differences were identified in middle school mathematics pre-service teachers' perceptions regarding the use of technology as a result of the training related to technology integration in mathematics teaching. Based on the findings, it was concluded that trainings that incorporate technological, pedagogical and content knowledge that are provided during teacher training process develop pre-service teachers' perceptions related to the use of technology in mathematics teaching.