Abstract: In this study, soaking solutions prepared from rosemary, clove, and mint extracts were used for the pretreatment of Undaria pinnatifida. Combined with electronic sensory analysis and gas chromatography-mass spectrometry (GC-MS) techniques, the effects of different extract addition amounts, solid-liquid ratios, and soaking times on the quality and deodorization effect of Undaria pinnatifida were analyzed, and the optimal pretreatment process was screened out. The results showed that the optimal deodorization process was as follows: extract concentration of 4 g/L, solid-liquid ratio of 1:4, and soaking time of 40 min. Mint and rosemary extracts exhibited color-protecting effects (ΔE<2, moderate color difference), while clove extract could improve the texture properties of Undaria pinnatifida (P<0.05). The electronic nose results indicated that the contents of nitrogen oxides and inorganic sulfides in Undaria pinnatifida soaked with clove and rosemary extracts were the highest. A total of 52 volatile compounds were identified in Undaria pinnatifida by GC-MS, among which 6 were key flavor substances. Rosemary extract reduced the contents of fishy substances such as hexanal, 1-pentanol, and 2-heptanol in Undaria pinnatifida, and increased the contents of floral and fruity compounds including 3-octanone, β-ionone, 1-octen-3-ol, eugenol, eucalyptol, and 4-allylanisole. This study provides a theoretical basis for deodorization and quality preservation during the deep processing of Undaria pinnatifida.