Objective: The aim of this study was to investigate whether the Swedish MD. Anderson Dysphagia Inventory (MDADI) is able to detect changes in dysphagia symptoms over time for patients with head and neck cancer (HNC). Methods: One hundred and forty-two patients with resectable tumors of the oral cavity were included prior to treatment. The patients filled out the MDADI, European Organization for Research and Treatment of Cancer Quality of Life questionnaire Core 30 (EORTC QLQ-C30) and the HNC module (H&N35) at baseline and at least one follow-up at 6 and/or 12 months after oncologic treatment. A control group without dysphagia (n = 115) was included. Results: Self-perceived swallowing function decreased in all domains at 6 months, and improved between 6 and 12 months. The changes were similar to the changes of the EORTC domains, indicating a sensitivity to change. However, even if improvements were seen at 12 months, the values were still inferior compared to baseline values, and the values of a control group without dysphagia. Convergent validity was found with values of the MDADI and EORTC domains producing similar results, and moderate correlations as hypothesized. Patients with moderate-severe dysphagia according to the MDADI (<60 points) demonstrated inferior values of the EORTC domains compared to patients with scores above 60 points. Conclusion: The Swedish MDADI was found to be sensitive to change, and showed convergent results when compared to other established instruments. The threshold value for the MDADI (<60 points) indicating moderate-severe dysphagia may be a valuable addition in the clinical use.