Since oil-in-water emulsions combine good cooling and lubricating capabilities, they have been commonly used in cold rolling nowadays. In order to understand the tribology characteristics of the emulsion during the cold rolling process, the effects of load, sliding speed, material of specimen, surface roughness and type of emulsion on the tribology characteristics of cold rolling are investigated by using the multi-purpose friction and wear tester.The P (load) ¡VV (sliding speed) curve was investigated under the conditions of load (below 2.4GPa), sliding speed (below 2.2m/s) at lower specimen roughness. Results show that QK-N36 emulsion can differentiate between boundary lubrication regime and initial seizure according to their friction coefficient, but RL-61 emulsion cannot differentiate them. Therefore, the load carrying capacity of RL-61 emulsion is better than that of QK-N36 emulsion, and its friction coefficient is also lower than that of QK-N36 emulsion. However, this tendency of experimental results is different from the cold-rolling practice.Under the lower load and higher surface roughness conditions with different hardness of specimen, the friction coefficient of RL-61 emulsion is higher than that of QK-N36 emulsion. This tendency of experimental results is the same as the rolling practice. Under the lower load condition with SDK-11 specimen, the friction coefficient of RL-61 emulsion varies gradually in the range of 0.07 ~ 0.09 located in the boundary lubrication regime, but the friction coefficient of QK-N36 emulsion reduces to 0.02~0.04 located in the mixed lubrication regime.