<p>The present study explores the interplay between metacognitive knowledge and growth mindset in foreign language vocabulary learning among a sample of 449 Chinese university students. Using latent profile analysis (LPA), the research identifies distinct learner profiles based on three dimensions of metacognitive knowledge (person, task, strategy) and three dimensions of growth mindset (commitment belief, positive self-talk, age-sensitivity beliefs). The LPA revealed three clear profiles for each construct: strategic regulators, emerging strategists, and passive learners for metacognitive knowledge; dynamic growth, mixed growth, and fixed growth for growth mindset. Regression analyses demonstrated that growth mindset variables, particularly commitment belief and positive self-talk, strongly predicted metacognitive knowledge dimensions, while metacognitive knowledge, especially strategy use, significantly predicted growth mindset outcomes. The findings highlight the multidimensional and interdependent nature of metacognitive and growth mindset in vocabulary learning, underscoring the need for integrated interventions that foster both strategic awareness and adaptive beliefs. This research contributes to theoretical understanding and offers practical implications for designing targeted support to enhance learner autonomy in second language vocabulary learning contexts.</p>