The aim of this study is to examine teachers' philosophical beliefs (PBs) about mathematics, the factors influencing the development of these beliefs, and their relation to teachers' beliefs and practices about teaching and learning mathematics.Data were collected through 229 questionnaires and five interviews.Analysis revealed a five-factor model, representing combination of the three dimensions of a model proposed by Ernest (1991).Four homogeneous groups of teachers according to their perceived importance were identified.A relative consistency was also found between teachers' PBs and their beliefs regarding teaching and learning Mathematics.However, inconsistencies between PBs and teaching practices emerged, which could be partially attributed to the factors influencing the development of PBs.Implications for the development of teachers' training programs regarding the affective domain and suggestions for further researcher are drawn.