Summary Invasive pneumococcal disease continues to be a major cause of morbidity and mortality among children and adults worldwide. Effective host defence against Streptococcus pneumoniae depends on immunoglobulin G-mediated phagocytosis of the bacteria and it has been shown in vitro that the Fc γ RIIA polymorphism (Fc γ RIIA-R131 vs Fc γ RIIA-H131) determines the capacity of immunoglobulin G2-mediated phagocytosis via this receptor. In this study, we evaluated Fc γ RIIA polymorphisms in children with pneumococcal sepsis and a number of control groups in order to investigate a possible association of Fc γ RIIA genotypes with Streptococcus pneumoniae infection. The distribution of the genotypes differed in these populations. The frequency of homozygosity for Fc γ RIIA-R/R131 in the patients was significantly higher than that in the healthy random donor population (43% vs 21%, P < 0.05). The frequencies of Fc γ RIIA-H/H131 were similar among all groups of individuals, while the incidence of the heterozygous Fc γ RIIA-R/H131 was lower (35% vs 52%, P < 0.05). Thus, it appears that the Fc γ RIIA-H131 polymorphic form, even in the heterozygous form, may be protective for pneumococcal sepsis and children with Fc γ RIIA-R/R131 genotype could be more at risk of infection with invasive Streptococcus pneumoniae.