Estimation model of rubber (Hevea Brasiliensis) tree volume compiled pursuant to one independent variable of stem girth. This study aimed to develop a model of mathematical equations to estimate the volume of rubber trees of clones GT 1, PR 255, PR 261, and the combined clones. The experiment was conducted at the Sembawa Research Station, South Sumatra. Sampling was purposive. The results showed that the volume of rubber tree clones of GT1, PR255, PR261 and mixed clones affected by stem girth at breast height and affected by clone. The model of PR255 clone volume, VPR255=0,5827G1,7182 (R2=95,6%), klon GT1 VGT1,(R2=97,8%), klon PR261 VPR261=0,5651G0,6471(R2=93,5%) and the mixed clones, V=0,5806G At replanting time, rubber wood has a potential used for sawn timber, plywood, veneer and MDF raw materials. The biggest utilization of rubber wood is for MDF raw materials, because in MDF processing all parts of the trees can be utilized. =0,5818G,5696 (R21,0352=98,6%).