Oral pyogenic granuloma is a hyperplastic inflammatory lesion commonly associated to local irritation or trauma. Females are more affected than men probably due to the vascular effects of hormones that occur during puberty, pregnancy and menopause. In the pregnancy, the lesions are known as "pregnancy tumor" and tend to occur more frequently during the second and third trimester. In the oral cavity, histopathological examination is required for diagnosis, since the lesion is clinically indistinguishable from other reactive lesions and, usually, there is no evidence of bone involvement. The authors report a rare case of pyogenic granuloma with destruction of alveolar bone mimicking a malignant tumor in a 20-year-old woman in the 19th week of pregnancy.