An electronic keyboard instrument includes a keyboard attachment frame section having a keyboard section; a rear frame section joined to a rear portion of the lower surface of the keyboard attachment frame section and having pedals provided at its bottom portion; and an electronic circuit that generates heat when activated and includes a power transformer and an amplifier. The electronic circuit is vertically provided on the inner surface of a rear body section of the rear frame section. Hole portions and ventilation holes are provided at a bottom portion of the rear body section. Ventilation holes are provided at the keyboard attachment frame section.