In this work, the design of anthropomorphic phantom coronary arteries for optimization of Computed Tomography Coronary Angiography (CTCA) is presented. First, a phantom vascular wall model for minimization of motion artifacts is manufactured. The mechanical properties of porcine coronary arteries and four soft rubber materials were tested and compared to each other, and the wall attenuation of tubular contrast-filled samples was characterized and compared to literature values as well. A coronary artery model was manufactured by segmenting the main coronary arteries from CT images, 3D printing a mold, and coating it in the rubber material with the most appropriate mechanical and CT attenuation properties. In the second part, the feasibility of 3D printing a phantom directly using four flexible commercially available materials is investigated. The CT attenuation properties match ranges for lipid-rich and fibrous plaque;​ thus the phantom can be used for optimization of non-calcified plaque imaging.