Abstract: To elucidate the effects of processing techniques on aroma and glycosidic aroma precursors in fresh tea leaves, fresh tea leaves with mixtures of one bud, two leaves and one bud, three leaves were plucked from Camellia Sinensis cv. zhuye at Shucheng tea plantation. The same batch of tea fresh leaves was divided into three batches and two of them were processed to green tea and black tea with the orthodox processing, respectively. The essential oils were extracted with SDE and analysis with GC/MS. Glycosidic aroma precursors were extracted and partially purified, then hydrolyzed with crude enzyme from fresh tea leaves in two-phase solvent system. The hydrolysis was extracted with ethyl ether and concentrated, analyzed and determined with GC/MS. The results showed that the component and content of aroma and glycosidic aroma precursors in fresh tea leaves, green tea and black tea are different. The total content of essential oils in fresh tea leaves, green tea and black tea was 17.263, 34.702 and 5.004, respectively. The components of algycone were benzyl alcohol, trans-linalool oxide, linalool, phenyl ethanol, methyl salicylate and geraniol in fresh tea leaves while those in green tea was five kinds as those of fresh tea leaves excepted benzyl alcohol and those in black tea were only phenyl ethanol and trans-linalool oxide. Compared with fresh tea leaves, the content of total algycone reduced 20.34% in the green tea processing. However, the content of total algycone reduces 95.60% in black tea processing. In made tea, the released aglycone contributed to the principal aroma component. Those results indicated that the composition and content of aroma and glycosidic aroma precursors in made tea changed with processing techniques.