In 2004, the countrys target is to fell down approximately 62,000 hectare of old rubber plantation. However, farmers tend to delay cutting down the trees due to high latex prices. It is more reasonable for the farmers to prolong tapping, but this will affect on countrys wood supply. To encourage more rubber wood consumption in country, the government should develop a standard green book of rubber wood to determine fair prices for farmers and wood manufactures. There are several steps to achieve rubber wood prices suitable for each local market. A preliminary specific wood weight calculated table should be able to tell farmers how to predict rubber wood value of their plantations and this manual will be more convenient for farmers to handle. For these reasons, an experiment was conducted using direct and visual measurement of wood volume and biomass of old rubber trees. The direct method was collected almost every part of a tree, root, stem, stem truck, branches, leaves and fruit. The results were able to derive a preliminary standard table of various diameter sizes and weights of RRIM 600 timber logs. The visual method was started by drawing a picture of the tree on a paper, then aimed with a pencil to level and wrote a slash cut of the tree into timber logs with approximately lengths of 1.05 or 1.35 meters (depended on trunk shape and branching formation of the tree). Next, the diameter sizes of each timber log was visual estimated and recorded. The base diameter of timber logs or tapping logs were easy to define by directly measure with a plastic tape, the following logs were defined gradually decreasing due to cone-shape of the tree and branches. Then, used the standard table to fill in the logs weight in corresponding with diameters, and timber shape), comprised usable logs into total usable weight of a tree, and multiplied by prices. Therefore, a total value of a tree will be possible to calculate and the total value of the whole plantation will be estimate.