OBJECTIVE To detect potential mutations of GCDH gene in five patients with glutaric acidemia type I (GA-I). METHODS Genomic DNA was extracted from peripheral blood samples from the patients. The 11 exons and their flanking sequences of the GCDH gene were amplified with PCR and subjected to direct sequencing. RESULTS Four mutations of the GCDH gene were identified among the patients, which included c.532G>A (p.G178R), c.533G>A (p.G178E), c.106_107delAC (p.Q37fs*5) and c.1244-2A>C. Among these, c.1244-2A>C was the most common, while c.106_107delAC was a novel mutation, which was predicted to be pathogenic by MutationTaster software. CONCLUSION The diagnosis of GA-I has been confirmed in all of the five patients. Identification of the novel GCDH mutations has enriched the mutational spectrum of the GCDH gene.