The autoimmune sequelae of rheumatic fever (RF) and rheumatic heart disease (RHD) are due to untreated or partially treated pharyngitis caused by Group A streptococcus (GAS). RF/RHD usually affects the genetically susceptible individuals. KIR (Killer cell immunoglobulin like receptor) of NK (natural killer) cell has been documented in susceptibility to various autoimmune diseases. KIR is of activating, inhibitory, pseudo and framework types. In here, 29 patients (pharyngitis, RF and RHD) and controls were studied to establish the association of different KIR genes in development of RF/RHD. KIR genotyping in all the disease groups revealed that the frequency of activating KIR2DS4A and inhibitory KIR2DL5B were less in RHD compared to the control.