The cumulative damage effect induced by cyclic freeze-thaw actions on geomaterials is a significant cause of engineering failures in cold regions. To investigate the internal damage and failure mechanisms of rock-like materials under freeze-thaw cycles, uniaxial compression tests and AE (acoustic emission) tests under uniaxial loading were conducted on cement mortar specimens simulating rock behavior. The influence of the number of freeze-thaw cycles on the mechanical and AE characteristics of such materials was studied. The results show as follows. The peak strength and frost resistance coefficient of the specimens decrease as the number of freeze-thaw cycles increases, with a more pronounced reduction after exceeding 40 cycles. Freeze-thaw cycles exhibit a cumulative effect on the damage and failure of specimens. Specimens subjected to more freeze-thaw cycles suffer more severe damage under uniaxial compression. With the increase in the number of freeze-thaw cycles, the crack propagation path evolves from simplicity to complexity, and the failure mode gradually develops from cracking to fragmentation and block spalling. Freeze-thaw action causes the specimens to enter a “continuous damage release” state earlier. With an increase in the number of freeze-thaw cycles, the cumulative values of ringing and energy rise, indicating an accelerated development in both the scale and intensity of micro-fracturing activity. The amplitude distribution of acoustic emissions in freeze-thawed specimens generally exhibits a “V” shape, with the peak frequency gradually shifting toward the dominant frequency band. With the increase in the number of freeze-thaw cycles, both the acoustic emission ringing count and energy at the moment of specimen failure show an exponential growth trend. In the range of 40~60 freeze-thaw cycles, the damage undergoes a key turning point from “slow accumulation” to “accelerated development”. The findings provide an experimental basis for the design, construction, and safe operation of geotechnical engineering in cold regions.