Abstract: Objective To explore the application value of 128-slice spiral CT in evaluating the stability of coronary plaque. Methods A total of 163 patients confirmed as coronary heart disease diagnosed by CT in our hospital were selected as study objects. They were divided into control group and observation group according to different diagnosis results, and 78 patients with acute coronary arteries syndrome were included in the control group, while 85 patients with stable angina pectoris were in the observation group. The number, types, CT value, and positive reconstruction rate of the plaque were compared between the two groups. Results A total of 365 plaques were detected in 163 patients in two groups, including 175 plaques in the control group and 190 plaques in the observation group. The proportion of type I plaques in the observation group was higher than that of the control group, and the proportions of type Ⅱ and Ⅲ plaques were significantly lower than that of the control group(P<0.05). The CT value of the observation group was(68.23±9.02)HU, which was significantly higher than(28.98±9.50)HU in the control group, and the difference was statistically significant(P<0.05). The positive reconstruction rate of the observation group was significantly lower than that in the control group, the difference was statistically significant(25.26% vs. 57.14%, P<0.05). Conclusion The 128-slice spiral CT applied in patients with coronary heart disease can help to effectively observe and identify the stability of plaques.