Financial literacy (FL) is increasingly being viewed as a key moderator in financial behavior models, especially in the context of digital finance. This study explored how FL affects the relationship between psychological, technological, and structural variables and financial decision-making through a systematic literature review. A total of 51 relevant studies were identified through a targeted search of the Web of Science Core Collection, and 9 empirical studies that met the strict criteria were finally included. The results showed that FL most often moderated the core relationships in technology adoption models (such as TAM and TPB) and also played a role in explaining behavioral constructs such as regret aversion and social influence. Although most studies showed that FL has a significant positive moderation effect, there are still inconsistencies in measurement methods and theoretical frameworks. This review points out that research in this field is still in its initial development stage, showing emerging but fragmented characteristics, and proposes that future research can be further deepened in terms of theoretical integration, measurement standardization, and context expansion.