Objectives: The first aim was to evaluate the stiffness of thyroid parenchyma with shear wave elastography (SWE) in patients with Graves disease (GD) and compare the elastographic values with those of asymptomatic volunteers. The second aim was to evaluate whether there was a correlation between SWE values and grayscale ultrasound (US) and laboratory parameters. Methods: In this prospective study, the thyroid gland parenchyma of 50 patients whose clinical and laboratory findings were indicative for GD and 54 asymptomatic participants with normal laboratory values was examined by SWE. Grayscale US images of the thyroid and submandibular gland were recorded. The volume of the thyroid gland was measured. Elastographic measurements were performed with a free region of interest. The quantitative SWE values (meters per second and kilopascals) of the patient and control groups were compared. A correlation analysis between the SWE values and grayscale US and laboratory parameters was performed. Results: The median (range) SWE values of the thyroid gland in patients with GD were significantly higher than those of the control group [17.34 (12.58–56.15) versus 12.05 (7.72–23.67) kPa and 2.28 (1.83–4.12) versus 1.92 (1.55–2.61) m/s; P <.001 for both comparisons]. When 14.5 kPa or 2.115 m/s was designated as the cutoff value, GD could be diagnosed with a high sensitivity and specificity. We showed a negative weak correlation between the SWE values and parenchymal echogenicity in the GD group. Conclusions: Shear wave elastography can be used as an effective imaging method with high sensitivity and specificity rates in the diagnosis of GD.