A communication apparatus includes: a first storage unit storing a received electronic mail; a verification unit executing a first verification about an electronic signature attached to the received electronic mail; a printing unit printing the received electronic mail if a verification result of the first verification is positive; a deletion unit deleting the printed electronic mail from the first storage unit; and a storage control unit controlling a second storage unit to store the mail information about the received electronic mail in the second storage unit if the verification result of the first verification is negative. The verification unit again executes the first verification about a specific electronic signature attached to a specific electronic mail which mail information is stored in the second storage unit. The printing unit prints the specific electronic mail if a verification result by again executing the first verification about the specific electronic signature is positive.