The effects of loading rate on the strength of frozen rock as well as the failure process at sub-zero temperatures were investigated. There was a marked difference observed in the fracture initiation stress and rock strength between frozen dry rock samples and frozen rock that contained water. There was no significant change observed in strength parameters of dry rock whereas in frozen rock containing water, rock strength increased with loading rate. Interestingly the magnitude of the change in strength was much greater for tensile strength than compressive strength of wet rock. It is postulated that these changes in mechanical properties may be explained in part by a reduction in the stress concentration within the interstitial spaces and cracks of the rock.