In the era of digital transformation and data-driven decision-making, big data analytics capability (BDAC) is crucial for firms to enhance innovation and sustainable competitive advantage in highly dynamic markets. Grounded in dynamic capability theory, this study used a moderated mediation model to explore the impact of BDAC on innovativeness. Empirical analysis was conducted by using survey data from 270 enterprises to test the hypotheses. The results reveal that BDAC significantly and positively influences innovativeness, and sustained innovation mediates this relationship. Moreover, organizational slack positively moderates the effect of BDAC on innovativeness, both the direct effect and indirect effect. These findings provide theoretical support and practical implications for understanding how BDAC enhances firm innovativeness.