Abstract: Glycosylphosphatidylinositol-anchored protein (GPIAP) plays an important role in many biological processes because of its diversity of structure and function. A GPIAP gene was isolated from Bambusa oldhamii using homologous cloning method, and designed as BoGPIAP. The full-length cDNA of BoGPIAP was 1772 bp including an open reading frame of 1 356 bp. The predicted protein encoded by BoGPIAP was 451 amino acids with a transmembrane structure at the N-end and a signal of GPI-anchor at the C-end, and also containing a typical conserved domain (47-211) and a CCVS motif, which indicated that it was a membrane protein belonging to GPIAP family. The plant expression vector with BoGPIAP::GFP was constructed and transformed into onion epidermal cells. The results of fluorescent microscope showed that the fused proteins were mainly located on the cytoplasmic membrane, which revealed that the protein encoded by BoGPIAP was a membrane protein. The expression vectors of sense and antisense BoGPIAP were constructed into the multiple cloning sites of pBI121 respectively, and transformed into tobacco mediated with agrobacterium. The transgenic plants of BoGPIAP were confirmed by PCR method. The phenotypes showed the antisense transgenic plants were thin, while the sense transgenic ones were stout comparing with the wild type. The average thickness of fibrous cell wall in the antisense transgenic plants was thinner, while that of the sense transgenic ones was significantly thicker than that of wild type, indicating that the BoGPIAP may play a regulatory role in the wall development of fibrous cell in bamboo.