A switch device includes a switch, a lead wire, a sealing member, and a housing. The switch includes a terminal provided on the outer side of the switch, the lead wire is fixed to the terminal, the sealing member seals a portion of the lead wire fixed to the terminal, and the housing is configured to house the sealing member. The housing has a first bottom surface and a second bottom surface. The first bottom surface has an opening through which the lead wire passes, and the second bottom surface is located closer to the switch than the first bottom surface. The sealing member abuts the second bottom surface.