BACKGROUND AND OBJECTIVES: Some patients stop statin therapy in spite of their doctors' advice. This study was designed to assess the pattern of lipoprotein profile changes and clinical characteristics of the patients who discontinued statin therapy. SUBJECTS AND METHODS: 69 patients (male 42.0%) were enrolled. The clinical characteristics and laboratory data on the lipoprotein levels were obtained from the medical records. RESULTS: The coexistence of diabetes mellitus (DM) was seen in 28% of the patients, hypertension was noted in 72% and coronary artery disease (CAD) was noted in 42%. The average lipoprotein levels during statin therapy were total cholesterol (TC)=163.8 mg/dL, triglycerides (TG)=174.3 mg/dL, high-density lipoprotein cholesterol (HDL-C)=34.8 mg/dL and low-density lipoprotein cholesterol (LDL-C)=94.2 mg/dL. LDL-C level increased by 44.9% at 2-3 months after ceasing statin therapy and by 54.6% at 4-6 months after ceasing statin therapy (p<0.01). The changes of the lipoprotein levels from baseline to 2-3 months and 4-6 months after discontinuation were +22.6% and +30.0% for the TC level, +20.8% and +24.0% for the TG level, and 0.06% and -0.65% for the HDL-C level respectively (p<0.01 for TC and TG, p=not significant (NS) for HDL-C). The achievement rate of target LDL-C level as suggested by the Adult Treatment Panel III (ATP III) of National Cholesterol Education Program (NCEP) was decreased 62.7% at 2-3 months and then it was decreased to 61.8% at 4-6 months after statin discontinuation. DM and CAD were more frequent in the patients who did not achieve the target LDL-C level even with life style modification. CONCLUSION: After statin discontinuation, TC and LDL-C were increased within 3 months. DM and CAD were highly prevalent in patients who didn't achieve their treatment goal.