Fresh natural rubber latex is tapped and collected from rubber plantations. Bacteria from environment and rubber tree bark will get into the latex and grows rapidly. Consequently, volatile fatty acid (VFA) is formed and will finally cause the latex to coagulate. Therefore, natural rubber latex purchasing market needs to determine of VFA which will take proximately 1-2 hours. This causes a waste of time and a cost for chemicals as well as labor. In this work, new method of using conductivity technique for measuring conductivity value of total ions in fresh natural rubber latex was investigated. It was found that the conductivity was coincidently increased as VFA in latex. Latex with high conductivity will also give a high amount of VFA. Therefore, measurement of conductivity of latex tends to be able to use for measuring the latex property, as a determination of VFA. This conductivity method offers an easy, convenience, less time and low cost.