An indoor unit of an air-conditioning apparatus, comprising: a body casing for receiving an indoor air-sending device configured to take in air and an indoor heat exchanger configured to exchange heat between refrigerant and the air taken in by the indoor air-sending device; and an outer shell panel (6, SP1, SP2) attached to the body casing, the outer shell panel (6, SP1, SP2) including: a front panel provided on a front surface portion of the body casing; and side panels (SP1, SP2) provided on side surface portions of the body casing, the side panels (SP1, SP2) each including: a base member (10, 20) provided on a side end portion of the front panel; a connecting member having a flat plate shape and has no light transmissivity, the connecting member including a first surface and a second surface formed on a side opposite to the first surface, and being attached to the base member (10, 20), the first surface located to face the base member (10, 20); a design panel having a flat plate shape and light transmissivity, the design panel being attached to a peripheral edge of the connecting member to be opposite to the second surface of the connecting member, and a band-shaped panel attached to the design panel to be stacked on the design panel, characterized in that the design panel including: a first surface portion, a second surface portion, and a connecting portion connecting the first surface portion and the second surface portion, the band-shaped panel being fixed to the connecting portion, and formed to extend from a front end of the design panel to a rear end thereof. a body casing for receiving an indoor air-sending device configured to take in air and an indoor heat exchanger configured to exchange heat between refrigerant and the air taken in by the indoor air-sending device; and an outer shell panel (6, SP1, SP2) attached to the body casing, the outer shell panel (6, SP1, SP2) including: a front panel provided on a front surface portion of the body casing; and side panels (SP1, SP2) provided on side surface portions of the body casing, a front panel provided on a front surface portion of the body casing; and side panels (SP1, SP2) provided on side surface portions of the body casing, the side panels (SP1, SP2) each including: a base member (10, 20) provided on a side end portion of the front panel; a connecting member having a flat plate shape and has no light transmissivity, the connecting member including a first surface and a second surface formed on a side opposite to the first surface, and being attached to the base member (10, 20), the first surface located to face the base member (10, 20); a design panel having a flat plate shape and light transmissivity, the design panel being attached to a peripheral edge of the connecting member to be opposite to the second surface of the connecting member, and a band-shaped panel attached to the design panel to be stacked on the design panel, a base member (10, 20) provided on a side end portion of the front panel; a connecting member having a flat plate shape and has no light transmissivity, the connecting member including a first surface and a second surface formed on a side opposite to the first surface, and being attached to the base member (10, 20), the first surface located to face the base member (10, 20); a design panel having a flat plate shape and light transmissivity, the design panel being attached to a peripheral edge of the connecting member to be opposite to the second surface of the connecting member, and a band-shaped panel attached to the design panel to be stacked on the design panel, a first surface portion, a second surface portion, and a connecting portion connecting the first surface portion and the second surface portion, the band-shaped panel being fixed to the connecting portion, and formed to extend from a front end of the design panel to a rear end thereof.