To determine whether the TIMI risk score correlates with the angiographic extent and severity of coronary artery disease in patients with non-ST-elevation acute coronary syndrome undergoing cardiac catheterization. We conducted a prospective review of 60 medical records of patients who underwent coronary angiography secondary to non- ST-elevation acute coronary syndrome between January and November 2015. Patients were classified into three groups according to TIMI risk score: TIMI scores 0 to 2 (group 1: n= 30), 3 to 4 (group 2: n= 19), and 5 to 7 (group 3: n= 11).We compared the coronary angiography findings of the three groups. Patients of group 1 had a greater likelihood of normal or non significant CAD than patients of group 2 (36% vs 13%, p < 0.001) and than patients of group 3 (36% vs 0%, p= 0.002). One-vessel disease was found more often in patients with TIMI score 0 to 2 than in patients with TIMI score 5 to 7 (28% vs 0%; p= 0.01), and in patients with TIMI score 3 to 4 than in those with score 5 to 7 (35% vs 0%, p= 0.006). However, 1-vessel disease was found in patients of group 1 as often as in patients of group 2. The frequency of two-vessel disease was similar whatever the level of TIMI score was low, intermediate or high. Three-vessel or left main disease was more likely found in patients of group 3 than in patients of group 2 (60% vs 26%; p= 0.01), and than patients of group 1 (60% vs 13%; p < 0.001). Chronic coronary occlusions and coronary calcifications were also more likely found in patients with TIMI score 5 to 7. In patients with non-ST-elevation acute coronary syndrome undergoing cardiac catheterization, the TIMI risk score correlated with the extent and severity of coronary artery disease. The author hereby declares no conflict of interest