According to one embodiment, the flexible printed wiring board of the one embodiment has a base, corrugated portion, and block. The base has therein a conductor that electrically connects a first end and a second end. The corrugated portion is formed in a middle part of the base and has a ridge and legs. The ridge is roundly bent. The legs continuously hang from opposite sides of the ridge. The block is located off the ridge within a gap where the legs face each other and is mounted on one of the legs.