Purpose: Systemic heparinization is a widely used technique on digital subtraction angiography (DSA). Heparin, however, is associated with a variety of complications, including hemorrhage, thrombocytopenia, and hematomas. This study aimed to investigate the safety and efficacy of micro-dose systemic heparinization or no heparinization on cerebral angiography for cerebrovascular diseases. Methods: A prospective, single-blind, randomized controlled study on patients who experienced transient ischemic attacks (TIAs) or acute ischemic strokes and underwent DSA is performed. Participants are randomized into three groups: regular-dose systemic heparinization, micro-dose systemic heparinization, and no heparinization. Information on patient demographics, laboratory tests, perioperative complications, and back pain scores is collected. Safety endpoints are defined as cerebral ischemic events and local complications of puncture site. Efficacy endpoints were defined as the recovery of the patients.