Abstract: The effects of GPA, anti-GPA IgG, α1acid glycoprotcin (α1-AGP), ovomucoid (OM) and wheat germ agglutinin (WGA) on the invasion of erythrocytes by P. falciparum were obseryed in vitro. GPA, anti-GPA IgG and WGA at low concentrations had obviously inhibitory effects on thc invasion. There were hyperbolic relationships between the concentrations of these inhibitors and their inhibition rates. OM, α1-AGP and non-spccific anti-serum had no obvious effect on the invasion. It is confirmed for the first time from the biological characteristics of receptor-ligand interaction that thc combination of GPA with P. falciparum merozoites has high spccificity, high affinity with a tendency to sa-turation and can produce specific biological effects.