Capillary isoelectrofocusing (CIEF) in the one-step mode and sodium dodecylsulfate-capillary gel electrophoresis (SDS-CGE) were applied to the analyses of proteins in the cerebrospinal fluid (CSF) and serum of patients with neurological disorders. The proteins with different isoelectric points and molecular weights were separated into their corresponding peaks on the CIEF and SDS-CGE electropherograms, and clinically useful information related to the damage in the central nervous system was obtained by examining the couples of CSF and serum samples by these high-performance capillary electrophoresis systems.