PROBLEM TO BE SOLVED: To provide a bathtub apparatus with illumination to/from which a light source can easily be attached and detached, or which can prevent water leakage to the light source. SOLUTION: The bathtub apparatus with illumination includes: a translucent bathtub; a connected light source provided with a flexible connector and a plurality of light sources supported by the connector; and a guide member provided with an insertion portion to/from which the connected light source can be inserted and removed and disposed circumferentially on the outer side of the bathtub. The connected light source is inserted and supported by the guide member so as to be inserted and removed to/from the insertion portion, and in the state of supporting the connected light source by the guide member, light emitted from the plurality of light sources disposed circumferentially on the outer side of the bathtub is transmitted through the bathtub and reaches the inside of the bathtub. COPYRIGHT: (C)2010,JPO&INPIT