Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen, of blood vessels and organs of the body, with particular interest in the arteries, veins and the heart chambers. This is traditionally done by injecting a radio-opaque contrast agent into the blood vessel and imaging using X-ray based techniques such as fluoroscopy.

The word itself comes from the Greek words angeion, "vessel", and graphein, "to write or record". The film or image of the blood vessels is called an angiograph, or more commonly, an angiogram. Though the word itself can describe both an arteriogram and a venogram, in its everyday usage, the terms angiogram and arteriogram are often used synonymously, whereas the term venogram is used more precisely.

The term angiography is strictly defined as based on projectional radiography; however, the term has been applied to newer vascular imaging techniques such as CT angiography and MR angiography. The term isotope angiography has also been used, although this more correctly is referred to as isotope perfusion scanning.