PURPOSE: To demonstrate the utility of ultrasound and color Doppler examination in differentiating red skin lesions. METHODS: We used high-frequency probes to identify common features of infantile hemangioma that can help distinguish it from other red skin lesions. RESULTS: In the pediatric population red skin lesions are frequently encountered in clinical practice. The most common red skin lesion is infantile hemangioma, which, in most cases, can be easily diagnosed clinically. An ultrasound examination is necessary to evaluate the lesion's depth or determine its proximity to nearby critical structures. Sometimes is not easy to differentiate it from other reddish lesions with a clinical examination alone. In recent years, thanks to the development of increasingly high-frequencies ultrasound probes, it has been possible to investigate them, evaluating their ultrasound characteristics and integrating them with those of the color Doppler examination. We highlight some ultrasound and color-Doppler features that can guide through differential diagnosis between infantile hemangioma and other clinically red skin lesions such as pyogenic granuloma, idiopathic facial aseptic granuloma, juvenile xanthogranuloma, congenital myofibroma and pilomatricoma. CONCLUSIONS: Ultrasound and color Doppler have proven to be useful tools to guide differential diagnosis between skin lesions with a reddish color that can't be clearly identified as hemangiomas with a physical examination alone.