Objective: The objective of this study was to determine the elasticity of sternocleidomastoid muscle (SCM) in patients with congenital muscular torticollis (CMT). Methods: In all, 41 patients and 22 controls were included in the study, and the elasticity of the patients’ SCM was measured. Echogenicity, thickness, and strain values of the SCM were also obtained. Results: The thickness and strain values of the SCM were higher in the patient group than in the control group ( P = .02 and P = .15). For median values, there was no difference in echogenicity and strain. In the strain elastography evaluation of the receiver operating curve (ROC) for muscle echogenicity in the isoechoic muscle group, the specificity and sensitivity were determined to be 100% and 22%, respectively, for the area under the curve (AOC) value of 0.558 (95% confidence interval [CI], 0.424–0.6686), and the cutoff value was <1.4. In the hyperechoic muscle group, the ROC for AUC values was found to be 0.542 (95% CI, 0.411–0.6686), and the cutoff value was >1.4 with 100% sensitivity and 20.75 specificity. Conclusions: The strain elastography technique can be used in the diagnosis of CMT.