The contemporary era of learning-oriented assessment (LOA) demands teacher professional efforts to appropriately and accurately assess learners' attainment and use the assessment results for the enhancement of learning. In second/foreign language (L2) discipline, this has recently brought language assessment literacy (LAL) to the forefront, emphasizing what assessment competencies L2 teachers with special needs, such as English as a Foreign Language (EFL) teachers, require to possess to be assessment literate. Given this, teachers' mastery of assessment practical and technical skills, as prescribed by the exiting LAL models, could not be entirely complete nor enhanced without their conceptions of assessment knowledge base and attitudes or beliefs about language assessment system. In light of this importance, the development of a LAL framework that helps better measure EFL teachers' affective and theoretical/conceptual dimensions of assessment is required. To illuminate these dimensions, the present study took insight from Xu and Brown's (2016) LAL model into the development and validation of a LAL scale which could have relevance to Iranian EFL contexts. To provide empirical support for the utility and validity of the scale, both exploratory and confirmatory factor analyses (EFA and CFA with SPSS and AMOS) were performed on data obtained from a sample of 213 Iranian EFL teachers. The results showed satisfactory internal consistency and construct validity of the scale, suggesting that it has the potential to be used for assessing EFL teachers' LAL conceptions and levels. The paper concludes with the importance of teachers' conceptions of LAL dimensions, and finally presents implications of the findings.