Familial Wolff-Parkinson-White (WPW) syndrome has an autosomal dominant inheritance. Previous genetic linkage studies showed the locus was on Chromosome 7 (7q3), and the gene was identified to be PRKAG2, which encodes for gamma-2 subunit of AMP-activated protein kinase (AMPK). The PRKAG2 mutation has been related to familial WPW syndrome with concomitant hypertrophic cardiomyopathy and/or atrio-ventricular nodal disease. There was no data about PRKAG2 mutation and familial WPW syndrome in Taiwan. Therefore, we report the status of PRKAG2 mutation in a family containing 2 siblings with documented WPW syndrome. Neither cardiac hypertrophy nor atrio-ventricular nodal disease was found in this family. Polymerase chain reactions were performed to amplify the translated region of the PRKAG2 gene. Denaturing high-performance liquid chromatography was subsequently used to screen for the presence of heterodulplexes, and DNA sequencing was applied to these heterodulplexes. No PRKAG2 mutation was identified in these family members, although four intronic single nucleotide polymorphisms (SNPs) were identified (in introns 2, 5, 9, and 16 respectively). In conclusion, this case report shows the absence of association between PRKAG2 mutation and isolated familial WPW syndrome (without concomitant hypertrophic cardiomyopathy and/or atrio-ventricular nodal disease).