During machining process or machinery operation, the lubricant quality will be degraded a large amount of debris and environmental changes. Poor lubrication may cause deterioration of machining quality or equipment damage. Therefore, in recent years, the condition monitoring of the lubrication system has played an important role in intelligent manufacturing. To describe the technology of lubrication condition monitoring clearly, this article will be separated into two parts which are cutting fluids and machining lubricants. The relationships between certain properties and qualities of lubricants will be discussed respectively. Also, the reasons for certain sensors were chosen will be explained. Finally, data from all the sensors will be demonstrated online the user interface of the lubrication condition monitoring platform, and then users will be able to set the alarm thresholds by themselves. With long-term data collection and observation, the warning basis for lubricant maintenance can be established.