Abstract: To investigate the effects of key processing techniques—namely boiling, drying, and vacuum freeze-drying—on the volatile flavor compounds of tender kelp during the processing of freeze-dried soup cubes, this study analyzed changes in volatile flavor compounds of tender kelp under various boiling times (0, 1, 2, 3, 4, and 5 min) and drying temperatures (60, 70, 80, 90, and 100 ℃). Furthermore, the study identified key volatile flavor compounds by calculating odor activity values (OAV). The results indicated that the boiling process significantly (P<0.05) reduced both the variety and the relative content of volatile flavor compounds in tender kelp. However, boiling time had no significant effect on the relative contents of aldehydes, acids, esters, and furans. In contrast, the relative content of ketones and 1-octen-3-ol significantly (P<0.05) decreased with increasing boiling time. The variation in the number of key flavor compounds in tender kelp across different boiling times was relatively minor. The OAV value of 1-octen-3-one was the highest among all samples, significantly exceeding that of other compounds, thereby indicating its critical role as the most important volatile flavor compound in boiled tender kelp. Its OAV value was lowest at a boiling time of 3 min. As the drying temperature increased, the number of types of volatile flavor compounds initially rose and then declined, with the 70 ℃ group exhibiting the most diverse range of flavor compounds. However, the content of each compound didn't follow a consistent pattern with variations in drying temperature. The OAV values of β-violet ketone and 2-undecanone were highest in the 60 ℃ group, while the OAV values of aldehydes and fishy compounds were relatively low, suggesting that 60 ℃ was the optimal drying temperature for tender kelp powder seasoning. The vacuum freeze-drying process didn't significantly (P>0.05) affect the variety, relative content, and composition of key flavor compounds in tender kelp, indicating this method didn't substantially alter the overall flavor. However, the OAV values of various compounds generally decreased, primarily leading to a reduction in flavor intensity. In conclusion, selecting a boiling time of 3 minutes and a drying temperature of 60 ℃ contributed to enhancing the flavor of freeze-dried soup cube products.