In accordance with the invention, method for cleaning and maintaining a medical, in particular dental, treatment instrument is provided, in which the instrument is cleaned with the aid of a cleaning agent (I) and is subsequently maintained by means of an oil-containing maintenance agent (V). In this connection, prior to supplying the oil-containing maintenance agent (V) in the first instance the cleaning agent is substantially completely removed in a rinsing step (III). As a result of the removal of the cleaning agent, it is possible to achieve a situation where the oil-containing maintenance agent can have a better effect. In particular, it is thus possible to reduce the risk that residues of the cleaning agent, which are still located in the interior of the treatment instrument after the cleaning process, negatively impair effective lubrication at sliding and bearing points of the treatment instrument by the oil-containing maintenance agent.
