To provide a driving device and an automatic opening and closing gate capable of being simply automated only by simply mounting a driving unit also to a horizontal pulling type opening and closing gate as well as a casement type without carrying out any large scale work and greatly reducing a manufacturing cost.

The driving device is constituted of a driving unit 3 unitized by driving wheels 30 and a driving motor 31 and a connecting means 4 for grounding the road surface G by its self-weight by mounting the driving unit 3 to a regulation member 20 of the opening and closing gate in a state to swivel up and down.