There is provided a contact device, and an electromagnetic switch in which the contact device is used, such that an arc generated between a fixed contact and a movable contact when the contacts are opened can be easily extinguished. The contact device includes a pair of fixed contacts (111), (112) fixedly disposed maintaining a predetermined interval inside an arc extinguishing chamber (102) and a movable contact (130) disposed so as to be connectable to and detachable from the pair of fixed contacts inside the arc extinguishing chamber (102), wherein a first arc root movement promotion portion (118b), (118c) that promotes movement in a direction away from the movable contact of the root of an arc generated when the contacts are opened and the movable contact moves away is formed on each of the pair of fixed contacts, and a second arc root movement promotion portion (130b), (130c) that promotes movement in a direction away from the relevant fixed contact of the root of an arc generated when the contacts are opened and the movable contact moves away from the pair of fixed contacts is formed on the movable contact (130).