The authors studied the behaviour of a few cerebrospinal fluid enzymes (GOT, GPT, LDH, ALP, CK, gamma-GT, PCHE) obtained from 26 patients without neurologic diseases. The stability of the enzymes has been verified in experimental various conditions, after store of the samples at different times and temperatures. This research has been carried in order to contribute to the determination of the reference values and to relieve their possible alterations.