Cerebrospinal fluid has a very important role in diagnosing various neurologic diseases. Since there are no official protocols concerning the turnaround time (TAT) for emergency tests of CSF and also no information on pre-analytical influence on test results, the main objective of this Thesis was to evaluate the influence of CSF time sampling on cytological results combined with influence of cell elements on biochemistry test results.The cell numbers were analyzed according to three different time intervals. After a 60-minute interval, the cells were counted in the Fuchs-Rosenthal counting chamber and with Sysmex XE 5000 Analyser, whereas only the Fuchs-Rosenthal counting chamber was used for measurements after 61-90 and after 91-120 minute time intervals. The biochemistry tests were conducted immediately upon the receipt of the samples and within the time interval of 91-120 minutes, both in a native sample without performing a centrifugation and in the supernatant without the cells after centrifugation. Glucose, lactate and total proteins were measured with Cobas 6000 c501 Analyser. The implementation of the MedCalc statistical software did not show any statistically relevant differences between cell numbers as counted in the chamber and those measured by the Sysmex XE 5000 Analyser. However, the tests showed that the number of cells counted after the interval of 91-120 minutes is smaller than the number of cells counted after the 60-minute interval, which is clearly visible both in total number of cells and in the number of big lymphocytes. It has been observed that the presence of cells in the sample has influence on the concentration levels of glucose and lactate, whereas the concentration levels of total proteins does not change in different measuring conditions. This study proved that the time of TAT for CSF can be prolonged up to 90 minutes, but when biochemistry test are done, the sample should be centrifuged.