Background: We have reported that a marked elevation in serum C-reactive protein (CRP) level is a predictor for infarct expansion and cardiac rupture after AMI. Although β-blockers prevent cardiac rupture after AMI, their effect on serum CRP elevation has not been determined. Methods: We studied a total of 154 patients with first Q-wave AMI. Patients complicated by pump failure were excluded from this study. Eighty-two patients received β-blocker treatment within 24 h of the onset of AMI, while 72 patients received no β-blocker treatment. Peak serum creatine kinase (CK) and CRP levels were determined by serial measurements. Results: There was no difference between the groups according to age, sex, coronary risk factors, pre-infarction angina, infarct site, prior use of cardiovascular drugs, use of revascularization therapy, and prevalence of multivessel disease. β-Blocker treatment was associated with a lower peak CRP level (6.9 ± 6.1 vs.10.8 ± 9.3 mg/dl, p = 0.002), a shorter duration from the onset to the peak CRP level (2 ± 1 vs. 3 ± 2 days, p < 0.0001), a lower incidence of cardiac rupture (p = 0.03) and lower in-hospital cardiac mortality (p = 0.02), despite similar peak CK levels. Conclusion: The early use of β-blockers is associated with decreased serum CRP level and a favorable clinical outcome after first Q-wave AMI, suggesting some beneficial effects of β-blockers on infarct healing after AMI.