In the polarographical study on the cerebrospinal fluid in 115 cases of various neuropsychiatric patients the author used the ratios N/D and H(2)/H(1) as the mutual general criteria for experimental results and obtained the following data: 1. In the primary reaction no polarographic peculiarity in the wave form, wave height, the ratio N/D (N = native wave height, D = denatured wave height) and the ration H(2)/H(1) (H(1) = the primary wave height, H(2) = the secondary wave height) due to various diseases could be recognized; but Tropp's crossing point was 16.0 mg% , in the general paresis revealing a fairly greater value in the general paresis than that in the case of schizophrenia. 2. In the secondary reaction it has been possible to divide various disease into two groups by the ration N/D. Namely, a general paresis group with the value under 0.6 and another schizophrenic group with value over 0.6. Furthermore, the relationship between Wasserman*s test and clinical symptoms on one hand and N/D on the other has been studied. 3. Filtrate of the cerebrospinal fluid seems to belong to the substance called mucoprotein by Winzler et al., but it is different from the filtrate of serum.