The International Society on Thrombosis and Hemostasis (ISTH) recently released the first ISTH guideline for antithrombotic treatment of COVID-19, which provides recommendations on anticoagulant and antiplatelet agents for patients with COVID-19 in different clinical settings. The target audience includes clinicians in internal medicine, intensive care, infectious diseases, hematology, vascular medicine, residents, family physicians, and other health care providers providing inpatient or outpatient care to COVID-19 patients. This article interprets the important parts of ISTH guideline.