Aim: Thyroid nodules (TNs) are abnormal masses of different structures and sizes to be detected promptly. The present study aimed to investigate the relationship between Bethesda and TIRADS and their diagnostic efficiency in histopathologically diagnosed malign TNs. Material and Method: 475 patients with TNs enrolled in this cross-sectional research. Laboratory parameters and clinical thyroid history were obtained from the automation system and analyzed retrospectively. They have been staged according to TIRADS, and the neck is evaluated in suspicious lymph nodes. FNAB results are then tracked for Bethesda staging. Results: TIRADS showed a good sensitivity at the rate of 74.5% and average specificity at 68.1% for TNs. Bethesda had a higher sensitivity at 80.1% and 95.2% specificity rates. The positive predictive (98.1 vs. 88.2) and negative predictive (13 vs. 23.6) values were higher for Bethesda than TIRADS. The diagnostic accuracy for Bethesda was 79%. According to the ROC, Bethesda had a more expansive area under curve (0.81) than TIRADS (0.63). FNAC was a better diagnostic method than ultrasonography in evaluating thyroid nodules (p