The aim of this study was to determine the influence of different cooling rates and trehalose concentrations on standard semen parameters after the freezing-thawing of ram spermatozoa. Ejaculates collected using artificial vagina from 4 Akkaraman rams were evaluated and pooled at room temperature. Semen samples diluted with a Tris-based extender containing different concentrations (50, 100 and 150 mM) of trehalose and no additives (control) were cooled to 5°C and frozen at slow (a rate of 0.5°C/min from 5°C to -25°C; -50°C/min from -25°C to -130°C), and fast (a rate of 10°C/min from 5°C to -25°C; -50°C/min from -25°C to -130°C) cooling rates and plunged into liquid nitrogen. Frozen straws were thawed individually at 37°C for 20 sec in a water bath for evaluation. In conclusion, 50 and 100 mM trehalose and slow cooling rate were found to significantly (p<0.05) improve the freezability of ram spermatozoa which were assessed regarding post-thawing sperm motility, morphologic sperm abnormalities, viability and membrane integrity. But, 100 mM trehalose concentration and slow cooling rate were observed superior than other treatment groups.