The infrared thermography technique was employed to analyze the ejection velocity characteristics of rock fragments in uniaxial compression testing. The velocity components of the fragments were found to be correlated with the infrared radiation characteristics of the rock sample during the loading process. The estimation of the initial fragment ejection velocity prior to the burst can be achieved by analyzing the peak temperature deviation and infrared radiation characteristics. Moreover, the assessment of the kinetic energy of fragments involved the consideration of both the initial ejection velocity and the mass of the pieces within each size group. The findings indicate that the velocity of a fragment is contingent upon the specific rock type and brittleness of the rock. The acceleration of the fragment movement in a rock is attributed to the propagation of stress waves and the opening of cracks, both of which contribute to the fluctuations in peak and average temperatures. Kinetic energy constitutes a fraction of the overall dissipated energy during a burst, and this fraction is directly linked to the average infrared temperature differential of the rock.