Grammar teaching continues to be a controversy matter in the field of teaching and teacher Education. It is generally agreed that attention to grammatical form is necessary and useful, but many issues related to teaching grammar still needs further research (Barnard & Scampton, 2008:59). This study investigated the relationship between Omani TESOL (teaching English to speakers’ of other languages) teachers’ attitudes towards grammar teaching and their grammatical knowledge. A questionnaire was used to collect data from 40 respondents teaching English in Omani schools. The findings showed that there was a positive correlation between teachers’ attitudes towards grammar teaching and their grammatical knowledge. However, there were no effect of gender on teachers’ grammatical knowledge and no effect of teaching experiences on attitude towards grammar teaching. The findings indicated that the final model of standard multiple regression showed that teachers attitudes towards grammar, gender, experience, age and the educational phase they teach in did not make a statistically significant unique contribution to the prediction of their grammatical knowledge. Such findings suggest directions for further studies in investigating the influence of language teachers’ attitudes/knowledge on their classroom practices. INTRODUCTION In recent years, grammar teaching has regained its rightful place in language curricula. Language teaching professionals are now of the belief that grammar cannot be ignored, and that without a good grammatical knowledge, learners’ language development can be severely constrained (Baleghizadeh & Farshchi, 2009). Grammar teaching and learning has attracted significant research attention. For example, many studies examined teachers’ explicit or declarative knowledge about grammar (e.g. Shuib, 2009; Andrews, 1994; Bloor, 1986). These studies showed that learners and teachers had encountered inadequate levels of grammatical knowledge. Other studies focussed on L2 and FL teachers’ beliefs about teaching grammar (Baleghizadeh & Farshchi, 2009; Borg& Burns, 2008). Borg and Burn’s (2008) study indicated that teachers expressed very strong beliefs in the need to avoid teaching grammar in isolation and reported high levels of integrating grammar in their practices. Baleghizadeh and Farshchi’s (2009) study revealed that teachers’ beliefs could be traced back to their long experience of teaching textbooks that heavily draw on deductive approaches to teaching grammar. Yet, we have to fully understand whether teachers’ attitudes towards grammar teaching have an influence on their grammatical knowledge. This is important because teachers’ attitudes/beliefs play a major role in influencing what they do in the classroom (Borg, 2006; Borg, 2003). Moreover, Shulman (1987) stressed that in order to teach grammar appropriately teachers need both grammatical knowledge and the skills “pedagogical content knowledge”. Thus, the current study focused on in-service TESOL teachers’ attitudes towards grammar teaching, and their grammatical knowledge to see if there is a correlation between the two and whether other background differences affect their knowledge of and attitudes towards grammar. This might help teacher educators to see the relationship as well as the impact of