Objective To explore the mechanism of anxiety in the relationship between daily living ability and marital satisfaction, and to provide a theoretical basis for improving the marital quality of the elderly. Methods A convenient sampling method was used to select 419 elderly people aged ≥60 years from Taiyuan, Jinzhong, Yuncheng and Jincheng in Shanxi Province as the research subjects. The Barthel Index (BI), Self-rating Anxiety Scale (SAS) and the marital satisfaction subscale of the ENRICH Marital Quality Questionnaire were used for the questionnaire survey. Results The score of daily living ability of the elderly was 100 (95.0, 100.0) points, the score of anxiety was 40 (33.8, 45.0) points, and the score of marital satisfaction was 39 (32.0, 46.0) points. There was a positive correlation between daily living ability and marital satisfaction. The mediating effect test showed that anxiety played a complete mediating role in the impact of daily living ability on marital satisfaction. Conclusion Improving anxiety can enhance the marital satisfaction of the elderly with declining daily living ability.