Methods and Study Design: This study will be a phase II, single-center, double-blind, randomized, placebo-controlled parallel-group study. In this trial, we are going to examine the possibility that lovastatin, a highly potent lipophilic statin, has disease-modifying effects in PD. We are going to enroll 80 patients with early stage PD patients. Subjects will then be randomized to a 48-week double-blind treatment period of lovastatin 80mg/day or placebo. Primary endpoints are changes in motor severity based on Movement Disorder Society-Unified Parkinson's Disease Rating Scale motor sub-score (MDS-UPDRS part III, with higher numbers indicating more severe disease). During the follow-up period, the dose of anti-parkinsonism could be added if both the patients and doctors thought the clinical condition deteriorated. Changes in PD medication as measured by levodopa-equivalent dose (LED) will be recorded at each visit. The secondary endpoints measured include MDS-UPDRS total scores, Part I and Part II sub-scores, the timing and dose of added anti-parkinsonism medication during the treatment period, the changes of 18F-DOPA PET uptake and MMSE scores, and global impression scale (GCI) of patients and investigators at the end of the study.