The Malaysian Education Development Plan (PPPM) 2013-2025 introduced 21st-century learning (21CL) to encourage teachers to be more progressive in implementing effective teaching and learning to achieve educational excellence. The teacher's understanding of the 21st-century learning implementation would determine effective teaching strategies in the classroom, especially for Islamic Education. Therefore, this study aimed to explore the understanding of primary school Islamic Education teachers towards the 21st-century learning implementation and further unravel the extent to which this understanding makes teachers' teaching more effective. A qualitative approach with an interpretive design was used to conduct this study. The research method used was the Hermeneutic.