Immunoblot technique was used in this study to detect IgE and IgG antibodies in human sera against mosquito antigens. Mosquito proteins were separated on SDS-polyacrylamide gels and transferred electrophoretically to nitrocellulose papers. After incubation with sera from different individuals, the precipitated bands were analyzed with enzyme-labeled goat anti-human immunoglobulins. Distinct patterns of antigen were recognized by IgE and IgG antibodies.