Abstract: The purpose of this study was to explore the key flavor compounds of the strong-aroma pomelo-scented Tieguanyin, and to clarify the effects of different scenting treatments on its quality. Based on the previous orthogonal test results and sensory evaluation, three samples with different quality levels were selected (the highest sensory score: O2-1, middle: O2-2, lowest: O2-3). The differences in sensory quality, main taste components and volatile substances were systematically compared by using the physicochemical detection and gas chromatography-mass spectrometry (GC-MS) combined with chemometrics. The results showed that the tea sample with the highest sensory score was processed with the following technique: 12 hours of aroma infusion, 60% flower addition, and drying temperature of 90℃ (corresponding to sample O2-1). This sample had a strong grapefruit flower aroma and a rich, mellow taste. There were significant differences in the contents of tea polyphenol and caffeine among the samples with different aroma infusion treatments (P＜0.05). A total of 233 volatile compounds were detected in the strong-fragrance pomelo-scented Tieguanyin, which were mainly esters, terpenes, and heterocyclic compounds, with 62 of them having a relative content over 1%. Linalool, dehydrolinalool, and indole were the main substances responsible for the pomelo blossom aroma. By combining the relative odor activity values with sensory evaluation, it was found that 2-isopropyl-3-methoxypyrazine and 2-thiophenemethyl mercaptan were the main sources of the green and fishy notes in dried tea, while 5-ethyl-3-hydroxy-4-methyl-2(5H)-furanone, methyl benzoate, and others were the important substances that gave the pomelo-scented Tieguanyin its floral and fruity aroma. The aroma gradient changes observed in sensory evaluation was basically consistent with the actual measured content change trend of volatile compounds. This study clarified the key flavor compounds of pomelo-scented Tieguanyin and the optimal scenting process, and revealed the effects of different scenting treatments on its flavor quality.