Agarwood oils are commonly extracted from low grade agarwood chips which are usually processed via distillation. They can be obtained from various aquilaria species such as A. Malaccensis,A.Hirta and A. Crassna. This viscous oil is called as pure agarwood essential oil (100% of extracted material)and pureness is one of key aspect taken into consideration for its price. The blending of a small amount of this precious agarwood oil with other essential oils such as Geranium,Sandalwood, Gurjum Balsam, Jasmine and Ylang Ylang can give rich, complex and pleasant oils. Agarwood oil acts as a base note to fix the perfume odour comprising of middle and top notes. Currently, there is no scientific technique used to differentiate pure and mixture agarwood oils and usually, it is based on traders and buyers agreement that may leads to inconsistencies. The present invention provides a method for classifying the fragrance quality of agarwood oils according to its odour quality into two separate groups pure and mixture using electronic nose coupled with a modified k-th nearest neighbour k-fold cross validation technique and substantial information from chemical constituent analysis using GCMS. This invention was covered in the patent filing PI 2014700916:Method for classifying the fragrant quality of wood as a product derived from agarwood. This invention anticipated to help the agarwood industries in order to support their products with scientific evident.