Background Guideline-based cardioprotective medical therapy is intended to reduce the burden of adverse cardiovascular and limb outcomes in patients with peripheral artery disease (PAD). However, contemporary data describing trends in use of medication remains limited. The present study, therefore, aims to investigate changes in use of cardioprotective medication in PAD. Methods and Results By using Danish national healthcare registries, we identified all patients with first-time diagnosis of PAD (1997-2016) and classified them into two groups: (1) PAD+ that includes all patients with PAD with a history of cardiovascular disease, ie, myocardial infarction, atrial fibrillation, and stroke (n=162 627); and (2) PAD (n=87 935) that comprise patients without a history of cardiovascular disease. We determined the use of medication in the first 12 months after the incident diagnosis of PAD and estimated age standardized 1-year mortality rates. Our results showed increase in use of cardioprotective medication throughout the study period in both groups. However, PAD+ had a higher use of medication (acetylsalicylic acid, 3.5%-48.4%; Clopidogrel, 0%-17.6%; vitamin K antagonists, 0.9%-7.8%; new oral anticoagulants, 0.0%-10.1%; Statins, 1.9%-58.1%; angiotensin-converting enzyme inhibitors, 1.2%-20.6%), compared with PAD (acetylsalicylic acid, 2.9%-54.4%; Clopidogrel, 0%-11.9%; vitamin K antagonists, 0.9%-2.4%; new oral anticoagulants, 0.0%-3.4%; Statins, 1.5%-56.9%; angiotensin-converting enzyme, 0.9%-17.2%), respectively. Furthermore, 1-year mortality rates in PAD declined with increased use of medications during study. Conclusions In this nationwide study, use of cardioprotective medication increased considerably with time, but compared to patients with other atherosclerotic diseases, there remains an underuse of guideline-based medical therapy in patients with PAD.