A switch designed for dustproof performance by minimizing a route of entry of dust from a terminal portion, includes a plurality of terminals, a movable contact piece that is supported in a manner allowing displacement between a non-conduction position and a conduction position, and a contact actuating member that displaces the movable contact piece in response to an externally applied pressing force. A main body of the switch includes an opening communicating with the outside, partition walls formed between the opening and the movable contact piece, barrier walls formed between the opening and the movable contact piece, and passages formed by ends of the barrier walls and walls that are opposite the ends of the barrier walls. Each partition wall extends across the corresponding passage and each terminal includes a connection portion and a blocking portion that is bent from the connection portion and blocks the corresponding passage.