Abstract: With the rapid development of the 64-row multi-slice spiral CT(MSCT) and dual-source CT(DSCT),CT coronary angiography(CTCA) for its non-invasive,convenient,low-risk and low-cost superiority in clinicalhas has been more widely used.But more complex cardiovascular imaging,often accompanied by higher radiation doses,which greatly increases the chance of suffering from malignant tumors.In recent years,CTCA radiation problem has been the concern of many scholars,the study of how low-dose CTCA done a lot of tube current and tube voltage regulation plays an important role in the CT low-dose coronary angiography,this paper reviews the current overall condition of the tube current and tube voltage parameter optimization applications,and that under the premise of ensuring the CTCA image quality for normal body mass index,heart rate and stable coronary artery calcification score in patients less than 100 AU,the use of lower tube voltage scan significantly reduce the radiation dose,if more combined ECG modulation current exposure technology will further reduce the radiation dose.However,higher obesity,weight,cardiac arrhythmia and calcification do not apply to low-dose CTCA check.