I n our country most workers are resident in rural areas and their is a little information about the combined effect of exposure to silica dust and bilhazial infection.EL Nasr glass and Crystal Company (Shobra El khema) was chosen for this purpose,130 workers were randomly selected from different departements of the factory.For each worker,a full occupational history, clinical examination,pulmonary function studies and X- ray chest were done.Urine and stool analysis and skin intradermal test was done for diagnosis of bilhazial infection.Immunoglobulin was also done. The pattern of immunoglobulin of silicotics either bilhazial or not showed a considerable increase in IgG,IgM and IgA antibodies .Also the pulmonary function tests in silicotics showed a mixed obstruction and restriction pattern.Immunological and pulmonary function studies revealed that the association of exposure to silica and bilhazial infection was not significantly differnet than the presense of each problem alone . This fact must be