Reducing low-density lipoprotein cholesterol (LDL-C) to target ≤1.81 mmol/L is a common therapeutic goal after acute coronary syndrome (ACS). This study aimed to examine the factors associated with reaching or not this LDL-C target after 1 year of optimal statin therapy postpercutaneous coronary intervention (PCI). This was a retrospective study of 633 consecutive prospectively enrolled patients with ACS treated between January 2011 and December 2012 at the Beijing Hospital (China). All patients were treated with PCI and statins for 1 year. A multivariate analysis was carried out to identify the factors associated with reaching the LDL-C target of ≤1.81 mmol/L. The rate of unreached LDL-C goal after 1 year was 48%. Compared with those who achieved their LDL-C goal, patients not achieving their LDL-C goal showed a higher proportion of females (37.9% vs 28.7%, P < 0.001), higher LDL-C levels at admission (2.82 ± 0.75 vs 2.08 ± 0.70 mmol/L, P < 0.001), lower proportion of patients with a history of PCI (17.6% vs 24.8%, P = 0.03), and younger age (66.7 ± 10.6 vs 68.9 ± 10.1 years, P = 0.009). A multivariate analysis showed that lower LDL-C levels on admission were predictive of LDL-C goal achievement (odds ratio [OR] = 4.81; 95% confidence interval [CI]: 3.46–6.70; P < 0.001), together with older age (OR: 0.98; 95% CI: 0.96–0.997; P = 0.026), and male gender (OR: 0.64; 95% CI: 0.42–0.98; P = 0.040). Higher LDL-C levels at admission, younger age, and female gender were independently associated with not reaching the LDL-C target after 1 year of optimal statin therapy after PCI.