Human Papillomavirus (HPV) infections are sexually transmitted diseases. Other than by sexual contact the virus can be transmitted through skin to mucosa contact or by saliva. The virus can belong to a high-risk or a low-risk genotype, depending on its ability for malignant transformation. Targeted cells are the basal epithelial cells on the skin or mucosa. HPV can come into contact with those cells only through micro-erosions on the epithelium. That is the reason the lesions are most commonly located on parts that are most exposed to friction. Because it is located deep in the epithelium and does not destroy host cells, it is well hidden from the organism's immune cells. HPV-related oral diseases include oral papilloma, condyloma acuminatum, warts and Heck's disease. These lesions are benign and look very similar. Except for Heck's disease, they can be recognized by their exophytic papillary structure. Apart from the benign ones, HPV also causes pre-cancerous and cancerous lesions. The most common potentially malignant lesion of the oral mucosa is oral leukoplakia, while the most common among cancerous lesions is oropharyngeal carcinoma, usually located on the tonsils. HPV can also be found on seemingly healthy mucosa not displaying any symptoms. Diagnosis is based on histopathological findings or deoxyribonucleic acid (DNA) evidence in the samples. The crucial part of the treatment is complete excision of the entire lesion. The most efficient method of prevention is vaccination, which has been in use for over 10 years.