Ascariasis, a geohelminthes infection in humans caused by Ascaris lumbricoides and occasionally by A. suum, is recognized as an important parasitic infection among children in the worldwide. In Sri Lanka, many cases have been reported among people in congested areas around Kalaniya and estates in up country. Diagnosis of Ascariasis is currently based on detection of Ascaris eggs in faeces. This study describes the extraction of Ascaris lumbricoides larval antigen and development of ELISA based on this larval antigen to improve the sero diagnosis of human ascariasis. The Ascaris larval antigen...