<p>Aquaculture households in island regions of Southeast China face significant threats to their economic stability and livelihoods from various stressors. However, there is a notable research gap regarding the combined effects of these stressors on island aquaculture households. This study adopts a participatory approach, integrating qualitative analysis of semi-structured interviews and quantitative analysis of questionnaire data, to explore how the interactions among multiple stressors affect the economic and livelihood conditions of seaweed aquaculture households in the island regions of Southeast China. The research revealed that these households were impacted by both climate and non-climate stressors, with rising temperatures, marine pollution, and market price fluctuations being identified as significant stressors. Qualitative interviews revealed the synergistic and cumulative effects of stressor interactions, such as between rising temperatures and marine pollution, as well as between market competition and technological constraints. These combined effects reduce aquaculture productivity, increase economic losses, shrink farming areas, and destabilize livelihoods. The study further conducted a quantitative analysis of the severity of the stressors, the exposure of aquaculture systems, and the sensitivity and adaptive capacity of households, providing insights into the economic risks faced by aquaculture households. Additionally, this study highlighted how the unique geographical characteristics of the islands intensify the impacts of these stressors. This study provides concrete evidence for developing policies and management measures to enhance the economic adaptability of island seaweed aquaculture households.</p>