Abstract Background: Persons with diabetes may have an elevated risk of Parkinson’s disease. Statin use could also modify the progression of Parkinson’s disease. Objective: The aim was to study whether there is an association between statin exposure and risk of Parkinson’s disease in persons with diabetes Methods: A nationwide nested case-control study of 2,017 Parkinson’s disease cases and their 7,934 matched controls with diabetes was performed using data from the Finnish Parkinson’s disease study (FINPARK). Persons with Parkinson’s disease were diagnosed between 1999–2015 and statin use (1995–2015) was determined from Prescription Register. In the main analysis exposure at least three years before outcome was considered. Cumulative exposure was categorized into tertiles, and associations were analyzed with conditional logistic regression. Results: Prevalence of statin use was similar in Parkinson’s disease cases and controls, with 54.2% of cases and 54.4% controls exposed before the lag time (adjusted odds ratio (aOR) = 1.02; 95% CI: 0.91–1.15). Those in the highest cumulative statin exposure tertile had higher risk of Parkinson’s disease than statin nonusers (aOR = 1.21; 95% CI: 1.04–1.42), or those in the lowest cumulative statin exposure tertile (aOR = 1.29; 95% CI: 1.07–1.57). Conclusions: Our nationwide study that controlled for diabetes duration and reverse causality does not provide support for the hypothesis that statin use decreases the risk of Parkinson’s disease.