alpha 1-Acid glycoprotein (AGP) and its concanavalin A-dependent four microheterogeneous fractions were measured in sera from women with ovarian carcinoma and those with an inflammatory ovarian disease. Total concentrations of AGP in inflammatory and cancerous sera were significantly higher than in control group, but did not differ from each other. In the fourth stage cancer the distribution of Con A-dependent fractions 1, 3 and 4 was significantly different as compared with control, second stage cancer and inflammatory groups.