Serum immunoglobulin (IgG, IgA, IgM) and complement (C3, C4) levels were determined in 61 sickle cell anaemia patients of various age groups and both sexes in their steady state by nephelometry. Serum IgG was found to be consistently elevated in 46% cases of all age groups. Increase in the levels of IgA, IgM and in the complement values (C3, C4) was also observed. Although the mechanism responsible for these variations was unclear, however, this study gave an idea about the general pattern of serum immunoglobulin and complement levels in sickle cell anaemia patients from the Eastern Province of Saudi Arabia.