The purpose of this study was to investigate the professional growth of the preservice and inservice Basic Education computer teachers. To understand their professional growth in terms of perception of teaching and competencies about pedagogic and subject matter knowledge, questionnaires were administered to 1,568 preservice teachers and 104 inservice teachers in Turkey. Mixed research method including both quantitative and qualitative traditions was used in this study. The researcher employed the questionnaires as the primary data collection tool but since questionnaires were limited in the representation of the whole picture, this study was complemented by interviews, observations and document analysis. Results revealed that preservice and inservice teachers' perceptions of teaching were generally positive about computer education. However, results indicated some negative points in their perceptions and competencies. Pertaining to the measured variables, there significant differences were found among preservice teachers based on their year in the program.This study elicited important results for preservice and inservice computer teaching.