It is hereby described an oral prophylactic device constructed of vulcanized natural latex or similar material, having a reinforced edge, a crown-shaped middle portion slightly thinner and a central portion representing a protuberance similar to a nipple (though bigger in size) which is absolutely flexible due to its lower thickness. It allows the practice of oral-vaginal or anal sexual intercourse without any risk of contagion of venereal diseases or AIDS and it also eliminates foul smells.