A bathtub exercise auxiliary apparatus includes: a first support, a bathtub, a second support, a traction unit and an exercise rack. The first support includes a plurality of base rods, traverse rods, longitudinal support rods, and longitudinal assembling rods. The bathtub is disposed in the first support and includes a trough and a plurality of housing portions. The second support is removably fixed to the first support, located above the bathtub, and includes a plurality of longitudinal connecting rods fixed to the longitudinal assembling rods, two parallel traverse connecting rods connected to the longitudinal connecting rods, two traverse rods connected between the longitudinal connecting rods, and two longitudinal rods connected to the traverse rods. The traction unit is disposed at the connections of the longitudinal rods and the traverse rods. The exercise rack is disposed between the traverse connecting rods, bridges over the trough, and includes a griping portion.
