Introduction: Anxiety is one of the most common psychiatric disorders in patients with cancer, and is very important in nursing. This study aimed at determining multimedia orientation tour on anxiety of patients with thyroid cancer receiving iodine therapy at Imam Khomeini Hospital complex of Tehran, during year 2017. Methods: This study was quasi-experimental, in which a pretest-posttest plan with a control group was used. All of the patients with thyroid cancer on iodine therapy, who referred to Imam Khomeini Hospital complex of Tehran in the first six months of 2017, were the statistical research community. Fifty patients were selected based on the inclusion criteria and purposive sampling method and randomly divided to two groups of experimental and control by using a table of random numbers. For the intervention group, the multimedia orientation tour was done through pamphlets and a video for 20 minutes. Patients filled Beck Spielberger's State Trait Anxiety Inventory (STAI) before and after the intervention. The SPSS statistical software SPSS 19 was used and chi-square, Fisher's exact test, and independent t-test and paired T were performed. Results: Results showed no difference between the two groups of intervention and control regarding demographic characteristics. The mean anxiety score was 96. 7 ± 6. 92 in the intervention group, and 97. 5 ± 3. 66 in the control group before the intervention, which respectively reached 74. 00 ± 8. 84 and 96. 3 ± 4. 3 after implementation of the intervention, and this difference was significant in the intervention group (P ≤ 0. 001). Conclusions: According to the results, it could be said that the multimedia orientation tour is effective in reducing anxiety in patients with thyroid cancer on iodine therapy. Therefore, it can be applied as a simple, non-invasive, low-cost and effective tool for reducing anxiety in patients with thyroid cancer on iodine therapy.