This thesis analyzes environmental impacts and the problem of storage and disposal of used motor oils. Used motor oils are hazardous waste and therefore, legally, they are classified in a special category of waste that requires special measures and actions to dispose it. The reason for this is that motor oils have a large capacity for pollution, and the compounds found in used motor oils are carcinogenic and can cause problems for the population if they are not adequately disposed of. Motor oils differ according to the method of production, and the main classification of oils is into mineral, semi-synthetic or synthetic motor oils. These are the three main types of motor oils, and each of these three main types has its own sub-types. Since motor oils are consumed during use, they need to be changed, and their disposal and storage must be carried out according to strictly prescribed procedures, since it is a matter of hazardous waste. Since used motor oils can cause significant pollution, intensive work is being done all over the world on ways to ensure that every drop of used motor oil is recycled and processed, and in addition to the recovery of motor oil, work is also being done to reduce the negative impact of motor oils on the environment.