For inborn errors of metabolism, high resolution melting analysis (HRMA) is a rapid, efficient, simple, and inexpensive method for mutation/rare variant screening. HRMA is a recent molecular technique for genotyping single-nucleotide polymorphisms without using probes. Here we apply HRMA to the α-galactosidase a (GLA) and glucose-6-phosphatase-alpha (G6PC) genes for mutation detection of patients with Fabry disease (MIM 301500) and glycogen storage disease type 1A (GSD1A; MIM 232200), respectively. To evaluate the procedure, genomic DNAs were blindly tested for known GLA mutations (c.658C>T, c. 679C>T, c.772G>A, c.796G>A, or c.718-719delAA) in three affected males and two obligate heterozygotes with Fabry disease, a G6PC mutation (c.247C>T) in a patient homozygous for that lesion, and 10 healthy control Turkish individuals. HRMA clearly detected the mutant amplicons and discriminated them from all wild-type GLA or G6PC amplicons. HRMA proved to be a sensitive, specific, and cost-effective mutation screening method for the rapid molecular diagnosis of these inborn errors of metabolism, indicating that the technique can be readily adapted to other genetic diseases.