In Asia, mammography following the injection of foreign materials into the breasts for cosmetic augmentation is frequently seen and diagnosis based on the typical radiologic findings is straightforward. We report the unusual radiologic findings in two patients with foreign body granulomas caused by injected foreign materials and discovered incidentally during screening work up. The mammographic findings were bilateral, hyperdense, spiculated masses, with occasional microcalcification, and at sonography, markedly hypoechoic, spiculated solid masses, located near the pectoralis muscle and partly extending into it, were observed. These radiologic findings mimicked malignancy.