The inherent odor of teak wood has repellent, and has an obvious effects on animals and human. In this work, the weight loss of volatile substances of different provenances teak including India, Nigeria and Thailand has been studied by TGA. The emmision of volatile substances starts at 30°C and ends at 100°C, lossing weight of the all samples are very less in the range of 100-200°C. When the temperature is in the range of 200-250°C, the hemi-cellulose and cellulose is pyrolyzed and the char starts to form. The results all the curves of TGA for the teak samples is similar, the sapwood losing weight is clearly higher than the heartwood for the same provenance teak. The volatile substances of sapwood are ranked as follows:V3071> V3070> V3072> V8024> V3074> V1009> V3078> V1007, and the heartwood: V3074> V3070> V1009> V8024> V3072> V3071> V3078> V1007.