The invention relates to a test method and a test device for the determination of an oil separation tendency of lubricating greases under pressure load. In the method, a predetermined test pressure is applied to a test volume (2) filled with lubricating grease (27) over a predetermined test period (32), the lubricating grease (27) of the test volume (2) is contacted with an oil absorption or oil separation element (11), and the change of the test volume (2) is detected on the basis of an absorption or separation of oil (29) separated from the lubricating grease (27) by the oil absorption or oil separation element (11) at the end of the test period (32). To be able to estimate the oil separation tendency of lubricating grease more exactly, in the method according to the invention, the time history of the change of the test volume (2) representative of the oil separation is detected over the test period (32).