Abstract: Phosphorus (P) is an essential macronutrient for plant growth and development. Phosphorus deficiency is a limiting factor for the rubber yield, and understanding molecular mechanism of rubber tree in response to phosphorus deficiency will be helpful to improve phosphorus use efficiency. According to EST from subtractive libraries for roots of rubber tree growing under phosphorus deficient conditions, the gene was cloned by RACE-PCR method and expression analysis was performed by quantitative realtime PCR. The author cloned a HbHyd gene in responding to phosphorus deficiency. Full length of HbHyd was 1860 bp, contained one ORF (open reading frame) with 1479 bp. The NCBI homology analysis showed that the deduced amino acid sequence of HbHyd was 84% identical to a castor (Ricinus communis) hydrolytic enzyme. The results showed that: HbHyd was up-regulated under phosphorus deficiency in the rubber tree roots. HbHyd was up-regulated in responding to phosphorus deficiency in the rubber tree. HbHyd would be helpful to improve phosphorus use efficiency.