eIF2A (eukaryotic translation initiation factor 2A) is a regulatory protein involved in the initiation of protein translation, primarily functioning as an alternative translation initiation factor under stress conditions. Unlike the canonical eIF2, eIF2A does not rely on GTP or the loading of initiator tRNA. Instead, under specific conditions such as endoplasmic reticulum stress, amino acid starvation, or viral infection, it mediates non-canonical translation initiation, facilitating the translation of specific mRNAs, such as stress-related proteins or viral RNAs. The function of eIF2A is closely linked to cellular stress responses, viral infections, and tumorigenesis, although its precise mechanisms and regulatory networks require further investigation. The activity of eIF2A may provide potential therapeutic targets for certain diseases, such as cancer and neurodegenerative disorders.