Theory can play a vital role in language learning and teaching because under the guidance of theory, it may be clear for teachers to gain insight into why and how to implement language teaching effectively. However, it is noteworthy that theory should be appropriately chosen, or the effectiveness of language learning and teaching will be decreased, so it can be essential to study a robust theory and conduct a critical review so that teachers can judge whether and how to apply it into language learning and teaching. For researchers, especially language teachers, it is valuable to study Bilingual Dual Coding Theory, so this paper aims to have a critical review on Bilingual Dual Coding Theory from the perspective of its background, nature, research method, development, and value. The conclusion is that Bilingual Dual Coding Theory can be called a robust theory after critically reviewing aspects above, but some weaknesses need noticing, e.g., relevant research is little; it is challenging to ensure research validity and reliability due to its relative complexity. Therefore, this theory needs more exploration, thus guiding practice in a more effective way. More importantly, researchers, especially language teachers, need have a constant critical reflection on theory.