The mean concentration of each of the serum protein-bound carbohydrates (hexose, hexosamine, fucose, and sialic acid) was significantly elevated in a group of 60 male schizophrenic patients. The total serum protein was elevated, ceruloplasmin was normal, and C-reactive protein was absent. Serum haptoglobin was significantly elevated. The distribution of haptoglobin types was normal. Haptoglobin concentration variation was significantly correlated with each of the carbohydrates and, to a lesser degree, with ceruloplasmin. In a group of 13 patients with normal erythrocyte sedimentation rate, the fibrinogen and haptoglobin concentrations were significantly elevated. There was no correlation between haptoglobin and fibrinogen concentrations in this group.