The English voiceless dental fricative /θ/, as in thought, thin, and theater, presents an engaging challenge for many Indonesian EFL (English as a Foreign Language) learners. This study explores the phonological, articulatory, and pedagogical factors contributing to learners’ struggles with accurately producing this sound. Since /θ/ is not part of the Indonesian phonemic inventory, learners often replace it with more familiar sounds such as /t/, /s/, or /d/, influenced by context and dialectal background. Drawing on learner reflections, acoustic analysis, and structured pronunciation tasks, this study investigates how native language influence and limited oral practice impact pronunciation. It also examines how visual modeling and explicit phonetic instruction support learner growth. Results show that focused feedback, guidance on tongue positioning, and auditory discrimination exercises significantly enhance learners’ awareness and production of /θ/. With continued practice and increased phonetic awareness, learners can successfully overcome this pronunciation challenge. The study highlights the importance of integrating targeted pronunciation instruction into communicative EFL classrooms to support learner development and confidence.