Objective To study the application value of spiral CT multi-phase enhanced scan in liver metastases. Methods The images of 103 patients with liver metastases who underwent spiral CT multi-phase enhanced scan in our hospital between January 2015 and January 2016 in our hospital were analyzed.Firstly, the patients underwent iodine allergy test and then they underwent CT examination in supine position, and the instrument was Toshiba 320-slice volume CT. After routine plain scan, standard dynamic three-phase scanning was performed. 80~100ml of nonionic contrast agent (300mgI/ml) was injected by upper intravenous bolus injection with high pressure injector, and the injection rate was 2.5~3.0ml/s. 20~30s after injection of contrast agent was arterial phase while 40~60s was portal phase and 150~180s was equilibrium phase. Results There were 552 lesions with marginal enhancement in arterial phase, 549 lesions in portal phase and 452 lesions in equilibrium phase. The relationship between the display rates of marginal enhancement between groups in arterial phase and equilibrium phase was arterial phase=portal phase＞ equilibrium phase (P＞0.05), the display rates of internal lesions and density differences of liver parenchyma around the lesions showed portal phase＞arterial phase＞equilibrium phase. Conclusion Multi-slice spiral CT is helpful to the detection, screening, diagnosis and differential diagnosis of liver metastases. It can significantly improve the clinical diagnostic rate, avoid the occurrence of misdiagnosis and enhance the role of information, which provides an important reference for clinical diagnosis.