Objectives: To assess the effectiveness of a high resolution ultrasound for temporomandibular joint (TMJ) evaluation in comparison to MRI in patients with TMJ disorders. Methods: Our study comprised 50 patients (35 female and 15 male) with a mean age of 30.61. Clinical examination was performed. Bilateral imaging of TMJ was conducted by using a high-resolution ultrasound and 1.5 Tesla MR. Diagnostic accuracy of ultrasound was assessed for disc displacement and joint effusion in comparison to MRI. Sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), and accuracy (Ac) were calculated for ultrasound. Measurements were compared by Bland & Altman and intraclass correlation coefficient (ICC). Significance level was set at p < 0.05. Results: Most frequent complaints were noise 42 (84%) and 34 (68%) pain. For disc position assessment with ultrasound for both sides and closed-open mouth, sensitivity, specificity, PPV, NPV and accuracy ranged between, 0.88 – 1, 0.60 – 0.87, 0.70 – 0.97, 0.75 – 1, and 0.84 – 0.98, respectively. For the diagnosis of effusion with ultrasound for both sides, sensitivity, specificity, PPV, NPV and accuracy ranged between 0.65 – 0.81, 0.91 – 1, 0.96 – 1, 0.45 – 0.46 and 0.72 – 0.84, respectively. ICC values calculated for intraobserver agreement for right and left TMJ for all measurements were found to be statistically significant (p < 0.001). ICC values ranged between 0.964 and 0.995 suggesting excellent correlation among ultrasound and MRI. In general, for ultrasound measurements we found a mean difference ranging between −0.182 and +0.130 mm in comparison to MRI. Conclusion: Ultrasound can be suggested as an adjunct to common imaging modalities in the assessment of TMJ.