In the cleaning and disinfection of endoscopes, the endoscope surfaces to be cleaned are successively(a) brought into contact with a cleaning solution which is heated to 55.degree. to 65.degree. C., kept at that temperature for 1 to 15 minutes and then drained off and which contains a low-foam nonionic surfactant, a proteolytic enzyme, at least one complexing agent and, optionally, other standard detergent constituents, and has a pH value of from 6 to 8;(b) brought into contact with a disinfectant solution which is heated to 55.degree. to 65.degree. C., kept at that temperature for 1 to 15 minutes and then separated off and which contains an aldehyde selected from the group consisting of formaldehyde and aliphatic C.sub.2 -C.sub.8 dialdehydes and at least one complexing agent, and has a pH value of from 6 to 8;(c) washed at least twice with water of which the pH value is adjusted to pH 6-8, the water being heated to 55.degree. to 65.degree. C. at least in the final wash cycle; and(d) dried with sterilized hot air at 55.degree. to 65.degree. C.,water having a hardness of from 3.degree. to 8.degree.Gh being used in steps (a) to (c).