Apolygus lucorum is currently a major pest of tea plantations, affecting the normal growth of tea shoots and reducing yield and quality. This study measured the effect of damage by A. lucorum alongside mechanical damage using UV spectrophotometry and high performance liquid chromatography. We found that the nutritional characteristics of tea varied with the level of bug damage, which influenced levels of caffeine, theanine, and tea polyphenols. As damage increased, caffeine content gradually increased. In contrast, theanine levels in highly damaged leaves were reduced compared to other levels of damage. The polyphenol level, like caffeine, increased with increasing damage. The levels of five other substances-Epigallocatechin, Catechin, Epigallocatechin gallate, Epicatechin, and Epicatechin gallate were all higher in tea with higher damage. Damage from A. lucorum changed the chemical profile of the tea, caused tea water turbidity, taste bitterness and decreased freshness, leading to the tea quality decline.