Rubber trees (Hevea brasiliensis) in Cambodia are important sources for not only natural rubber but also wood products. This study was conducted to set up stem volume equations to estimate the stand volume and the volume increment for rubber trees in Cambodia. Krek Rubber Plantation located in Kompong Cham Province was selected for study area. Sixty trees of the clone PR107 at the age of 36, 44, 45 and 46 were felled and cut into segments of one meter long to formulate the volume equation. The DBH and total height of 450 standing trees (15 plots) at different ages (6-10 and 36-48) were measured to estimate volume per hectare and the mean annual increment (MAI). This study revealed that the volume equation for standing rubber trees clone PR107 is V=0.00018381 D^<2.23961> H^<0.15334> or V=0.00024884 D^<2.29535> where V is the over bark volume (m^3), D is diameter at breast height (cm), H is total height (m). Using the two-variable equation, rubber wood volume at the rotation length of 25-30 years was estimated at about 240 - 270m^3 ha^<-1> with the MAI of 9.33 m^3 ha^<-1> yr^<-1>.