Total protein concentration in 284 samples of cisternal cerebrospinal fluid was evaluated by V. D. R. L.'s method of Bossak, Rosenberg and Harris. Statistical treatment of results permitted to stablish as average normal concentration, 20 mg/100 ml and the upper limit for physiological shifts, 30 mg/100 ml. Values 26% lower were obtained for most of these samples by the volumetric technic of Nissl, as modified by Kafka. Globulin changes appointed by colloidal reactions did not affect results as showed concentrations obtained by both methods. These data confirm former findings of the authors on safety of V. D. R. L's method concerning the instrument effective error and that of Bossak and co-workers on the ineffective influence of albumin-globulin ratio on total protein concentration obtained.