Abstract: A height adjustable pet bathtub is provided. The bathtub comprises a bathtub body, a work platform, and a lifting mechanism. The bathtub body defines a rinsing space, the work platform is positioned within the rinsing space, and the lifting mechanism is disposed in a wall of the bathtub body and connected to the work platform to move the work platform up and down. The invention allows for convenient cleaning of pets of different sizes, improving versatility and practicality.