The no-reflow phenomenon after primary percutaneous coronary intervention (PCI) is associated with larger infarct size, worse functional recovery, and higher incidence of complication after acute ST-elevation myocardial infarction (STEMI). The aim of this study was to assess the relation between preprocedural N-terminal pro–brain-type natriuretic peptide (NT–pro-BNP) and angiographic no-reflow phenomenon. We measured preprocedural serum NT–pro-BNP level in 159 consecutive patients with acute STEMI (aged 63 ± 12 years; 72% men) before PCI. Angiographic no-reflow after PCI was defined as Thrombolysis In Myocardial Infarction (TIMI) flow grade <3. Baseline characteristics, including time from chest pain onset, between the no-reflow (n = 67) and normal-reflow groups (n = 92) were similar. NT–pro-BNP was significantly higher in the no-reflow group than the normal reflow group (1,982 ± 3,314 vs 415 ± 632 pg/ml; p = 0.005). Also, high-sensitivity C-reactive protein, monocytes, and troponin-T were significantly higher in the no-reflow group than the normal-reflow group. In the no-reflow group, NT–pro-BNP was much higher in patients with TIMI flow grade 0 (n = 41; 2,290 ± 3,495 pg/ml) than those with TIMI grade 1 or 2 (n = 26; 1,575 ± 2,340 pg/ml), but without significant difference. The area under the receiver-operating characteristic curve for NT–pro-BNP was 0.78, and the optimal cut-off value identified using receiver-operating characteristic curve analysis was 500 pg/ml. At the standard cut-off value of >500 pg/ml, increased NT–pro-BNP showed a high probability of no-reflow phenomenon (odds ratio 4.42, 95% confidence interval 1.15 to 17.00, p = 0.028). In conclusion, preprocedural NT–pro-BNP may be a strong predictor of the development of no-reflow phenomenon after PCI in patients with acute STEMI.