We report here an 8-year-old patient with acute coronary syndrome (ACS) who was diagnosed with homozygous FH (HoFH) due to mutations in the low-density lipoprotein receptor (LDLR) gene and subsequently treated with percutaneous transluminal coronary angioplasty (PTCA) after filtration plasma. The gene discussed is LDLR; the disease is acute coronary syndrome.