Objective To analyze the value of CT angiography (CTA), treadmill exercise ECG testing (TET) and dynamic electrocardiogram in the diagnosis of silent myocardial ischemia (SMI). Methods Sixty-four patients with suspected SMI who were admitted to the hospital from January 2014 to February 2018 were selected. All patients underwent CTA, TET and dynamic electrocardiography. With coronary angiogram (CAG) as the golden standard, the detection accuracy, sensitivity and specificity were compared among CTA, TET, dynamic electrocardiogram and TET combined with dynamic electrocardiogram. Results The sensitivity, specificity, accuracy and Kappa value of CTA were 96.61% (57/59), 100.00% (5/5), 96.88% (62/64) and 0.82, respectively. Those of TET were 84.75% (50/59), 100.00% (5/5), 85.94% (55/64) and 0.46, respectively. Those of dynamic electrocardiogram were 83.05% (49/59), 60.00% (3/5), 81.25% (52/64) and 0.25, respectively. Those of TET combined with dynamic electrocardiogram were 89.83% (53/59), 80.00% (4/5), 89.06% (57/64) and 0.48, respectively. The accuracy and sensitivity of CTA were significantly higher than those of TET and dynamic electrocardiogram (P<0.05), but there was no significant difference, compared with TET combined with electrocardiogram (P>0.05). Conclusion Compared with TET and dynamic electrocardiogram, CTA has higher accuracy in diagnosing SMI, but the accuracy and sensitivity of TET combined with dynamic electrocardiogram are similar to CTA. CTA can be used as a supplementary examination.