The current study tested the hypotheses that knee osteoarthritis (OA) patients and spouses who report more spousal understanding of patient's pain would report greater marital satisfaction. A total of 124 couples completed interviews at three time points across 18 months. Results from dyadic analyses showed that patients who felt more understood by their spouse report, and have spouses who report, higher marital satisfaction concurrently. In addition, patients who felt more understood by their spouse reported higher marital satisfaction over time. Spouses' reports of understanding also had a significant influence on the patients' and their own marital satisfaction concurrently. Results highlight the importance of spouses understanding knee OA patients' pain for both dyad members' marital satisfaction.