Abstract: DELLA protein belongs to the plant-specific GRAS family and is a negative regulator of plantgrowth. To reveal the molecular regulation mechanism of DELLA gene in rubber tree growth and development,the full-length c DNA sequence of HbRGL1 was cloned from rubber tree cultivar Reyan 7-33-97. The ORF of HbRGL1 was 1 851 bp,and encoded 616 amino acids. Bioinformatics analysis showed that HbRGL1 was anunstable hydrophilic protein containing two conserved domains of DELLA and GRAS,and localized in thenucleus. Phylogenetic analysis showed that HbRGL1 was clustered with Hb GAIL of rubber tree,Me GAIL ofManihot esculenta,Rc GAI of Ricinus communis,and Jc GAI of Jatropha curcas. q RT-PCR analysis showed thatthe expression level of HbRGL1 in different tissues of rubber tree was significantly different,and its expressionlevel was the highest in flower. HbRGL1 expression was significantly up-regulated in leaves treated by differenthormones such as auxin（IAA）,ethephon（ET）and abscisic acid（ABA）. Especially,and it rapidly respondedto GA3treatments,and had the highest up-regulation of expression level. The study provided theoretical basisfor further elucidating the function of HbRGL1 in the growth and development of rubber tree.