In teaching, innovative work behavior is an important issue and there is a crucial role of teachers for development of innovations. Purpose of this study is to assess role of teachers beliefs and personality for innovative work behavior among school teachers. Participants were 400 secondary school teachers of 28 schools at Kolkata (West Bengal, India), who were administered the following measures: a) Innovative Work Behavior Scale (Janssen, 2000), b) Belief-Assessment Scale for Innovation and c) Neo Five Factor Inventory (Costa & McCrae, 1992). The Belief-Assessment Scale for Innovation was developed for this study. Teachers belief for innovation, openness, extra-version, and conscientiousness were found to be positively correlated with all the three domains of innovative work behavior i.e. idea generation, idea promotion, and idea realization. Neuroticism was negatively correlated with idea generation. Regression analysis revealed that teachers beliefs for innovation and degree of openness to new or different ideas have a potentially significant impact on innovative work behavior. This study is a significant contribution towards understanding the determining factors of innovative work behavior among teachers.