Christianson syndrome is a rare X-linked disease caused by mutations in the SLC9A6 gene. The clinical manifestations are male developmental delay, language disorder, seizures, mental retardation, ataxia, microcephaly and so on. Two cases of male children with Christianson syndrome were reported. The proband was 1 year and 11 months old. Clinical manifestations include microcephaly, global developmental delay, and seizures. The electroencephalogram showed that the central midline region of spikes and slow waves were emitted, and all exons sequencing detected a mutation in the SLC9A6 gene chrX: 135084373 [c.803+1(IVS6)G>A]. The proband′s brother was 4 years and 8 months old. The clinical manifestations were similar. The electroencephalogram showed spikes and spines in the Rolandic area on both sides. Slow waves and spiny slow waves were emitted. Magnetic resonance imaging suggested brain atrophy. The genetic verification results were consistent with the proband. The SLC9A6 gene c.803+1(IVS6) G>A splicing mutation was a pathogenic mutation in this family.