A keyboard instrument including a musical instrument case, a speaker which emits sounds in response to instructions from a keyboard section, and a keyboard lid which is switchable between a first arrangement state where the keyboard lid covers at least a portion of the keyboard section and a second arrangement state where the keyboard lid is opened to expose at least a portion of the keyboard section and housed in the musical instrument case, in which the keyboard lid in the second arrangement state is arranged such that a first acoustic space for leading the sounds emitted from the speaker to outside of the musical instrument case is formed between the keyboard lid and a portion of the musical instrument case.