A full-length cDNA of GGPPS gene from Tripterygium wilfordii suspension cells was obtained by use of RACE strategy (GeneBank: KM978333), and then analyzed by bioinformatics approaches. TwGGPPS cDNA has 1857 nucleotides and an open reading frame (ORF) encoding a protein of 514 amino acid residues. The deduced protein has isoelectric point (pI) of 7.85, a calculated molecular weight about 57.13 kD, 5 conserved domains and 2 functional domains. PSORT Prediction showed it was located at plasma membrane. Phylogenetic analysis demonstrated that TwGGPPS1 was similar to GGPPS from other species of plants. For the first time the cloning of geranylgeranyl diphosphate synthase gene from T. wilfordii was reported, it lays the foundation for further research of diterpenoids biosynthetic pathway.