The invention provides a self-adaptive colorimetric pool, which belongs to a spectrophotometry colorimetric pool. The self-adaptive colorimetric pool comprises a body and an upper cover, wherein the upper cover is covered on the body, the body is provided with a colorimetric pool groove with an upward opening, a light inlet port communicated with the colorimetric pool groove is formed on the leftend of the body, a detector port communicated with the colorimetric pool groove is in arrangement corresponding to the light inlet port and is formed on the right end of the body, the front side of the body is provided with a circular roll accommodating groove communicated with the colorimetric pool groove, a self-adaptive circular roll is arranged in the circular roll accommodating groove, and the self-adaptive circular roll is arranged in the circular roll accommodating groove in a way that the self-adaptive circular roll per se can rotate through an elastic part which exerts the elasticityin the direction towards the colorimetric pool groove to the self-adaptive circular roll. The invention reaches the effect of consistent position of the same colorimetric cuvette when being inserted into a detection system for many times, the accuracy and the precision of the instrument are improved, and the invention can be widely used in a spectrophotometry analysis instrument.