Natural rubber harvested from the rubber tree is one of the most economically important agricultural products for Thailand. Factories using primary rubber products especially rubber sheets and block rubber encounter problems associated with fungal growth and often receive public complaints about the malodor they generate as well as other environmental concerns. In this study, the use of wood vinegar produced from rubber wood to ameliorate these problems was investigated. Its efficiency as an antifungal agent was determined from the number of counts of fungal colonies formed per cm2 and per gram of material, on rubber sheets and block rubber respectively. To analyze the effect of wood vinegar on malodor from block rubber processing, shredded rubber samples were prepared and the organic acids contained in the gas released during the rubber drying process were measured. The results showed that wood vinegar can significantly decrease the numbers of fungal colonies on rubber sheets and shredded rubber. A 5.0% application of wood vinegar which reduced fungal growth during the storage of shredded rubber also reduced the malodor from the drying process. The ability of wood vinegar to reduce fungi and the organic acid content of the air released during the rubber drying process is due to the presence of phenolic compounds and acetic acid. Thus soaking in wood vinegar is an effective way to deal with these problems and shows a very high potential to do so without any significant toxicity.