The differences in the immune response between body lice, Pediculus humanus humanus, and head lice, Pediculus humanus capitis, were regarded as primary factors determining their differential vector competence. To find any differences in genetic components in immune system between body and head lice, whole genome sequences of head lice were determined by both SBS [sequencing by synthesis, Illumina Genome Analyzer (Illumina-GA)] and pyrosequencing (Roche GS FLX), and compared with the reference genome sequences of body lice. The short DNA reads from Illumina-GA (an average mapping depth of 50-fold) were aligned first to the body louse reference genome, to which Roche GS FLX DNA reads (an average depth of 2.5-fold) were subsequently assembled to make up gaps between mapped consensus. Total consensus showed a size of 114 Mb and a coverage of 96% of the published body louse genome sequences. From this head louse genome sequences, a total of 12,651 genes were predicted and used for comparing with the 10,775 genes previously reported from the body louse genome. The homolog analysis identified 873 head louse-specific genes and 422 body lice-specific genes. Comparison of immune response genes between both louse species showed head lice have more number of immune-related genes than body lice. Head lice were determined to possess all of the 107 immune-related genes reported in the previous study (Kim et al., 2011), suggesting that there is no difference in genetic make-up in terms of the 107 immune-related genes between body and head lice.