The present application relates to the field of household appliances and discloses a hinge and an opening and closing device. The hinge includes a first hinge seat, a second hinge seat, a sliding member, and an elastic member. The first hinge seat has a first matching structure, the first matching structure has a first curved surface and a first matching surface; the second hinge seat has a first accommodating cavity extending in a first direction, an end of the first accommodating cavity having a first opening; the sliding member is provided in the first accommodating cavity and the sliding member may slide in the first direction. The sliding member has a second matching structure, the second matching structure has a second curved surface and a second matching surface, and the second matching structure is connected to the first matching structure through the first opening.