Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder with strong genetic components. The present study comprises the detection of four single nucleotide polymorphisms (SNPs) in GRIK2 followed by a family-based association analysis of the SNPs in 126 Korean ASD trios by using the transmission disequilibrium test (TDT) and haplotype analysis. We found preferential transmission of the C allele at the rs3213607 (P<0.001) of GRIK2 in ASD and haplotype analysis revealed that one haplotype demonstrated a significant association (P=0.023). These results suggest a potential association between GRIK2 and ASD in the Korean population.