To address the fishy odor of large yellow croaker (Larimichthys crocea), this study investigated deodorization via yeast fermentation using high-activity dry yeast as the fermentation strain. Single-factor experiments were conducted to evaluate the effects of fermentation temperature, fermentation time, and yeast dosage on sensory scores and product freshness. Subsequently, the fermentation parameters were optimized using response surface methodology, with sensory scores used as the response variable. Under the optimized conditions, differences in color, pH, water-holding capacity (WHC), cooking loss, textural properties (hardness, springiness, chewiness, and gumminess), free amino acid (FAA) composition, and volatile compounds in large yellow croaker before and after fermentation were further analyzed. The optimal fermentation conditions were determined to be a temperature of 28 ℃, duration of 55 min, and yeast addition level of 1.75%. Under these conditions, fermentation enhanced textural characteristics and color attributes, with WHC increasing by 4.14% and cooking loss decreasing by 3.11%. FAA analysis showed that the total free amino acid content decreased by 154.07 mg/100 g after fermentation, with the umami, sweet, and bitter amino acid contents decreasing by 9.9, 61.33, and 74.62 mg/100 g, respectively, and the proportions of umami and sweet amino acids increasing by 4% and 0.52%, respectively. SPME/GC–MS analysis demonstrated a significant reduction in fishy aldehydes (nonanal, heptanal, pentanal, and hexanal) and a substantial increase in pleasant fermented aroma compounds (alcohols, ketones, and esters). In summary, yeast fermentation effectively improved the flavor profile and product quality of large yellow croaker. This study provides a theoretical basis for the application of fermentation-based deodorization technology in large yellow croaker processing.