A door closing device (10) for an automatic closing of a door leaf (B) coupled with a floor and/or a doorpost (S) so as to swing. The door closing device (10) comprises a fixed unit (12) that is fixed on the floor and/or the doorpost (S), a translating unit (14) and a rotating unit (16) on which the door leaf (B) is fixed. The coupling of the three units (12, 14, 16) and the presence of spring (38) are such that, when the rotating unit (16) rotates in a first sense of rotation, the translating unit (14) is caused to translate in a direction and such that, when the translating unit (14) translates in an opposite direction, the rotating unit (16) is caused to rotate in an opposite sense of rotation.