The global tea (Camellia sinensis L.) output has been in decline despite the continued increases in global tea consumption amount and cultivation area. Application of potassium (K) fertilizer is a common way to enhance tea yield and quality, given the widespread deficiency of soil-available K in tea plantations. However, the specific effects of K fertilizer application upon tea yield and quality and its differential effects among varied K fertilizer application amount, soil-available K amount and tea types remain unknown. In this study, 518 pairwise comparisons between tea productivity after non-application and application of K fertilizers were obtained through a literature review, and then analyzed. The results showed that K application had a significant positive effect on tea yield and overall quality, enhancing the amount of tea yield, the content of amino acid, tea polyphenol, water extract, and catechin by 7.83 %, 7.84 %, 26.79 %, 1.57 % and 6.47 %, respectively. Furthermore, a K application rate of 90–120 kg ha⁻¹ maximized the tea yield and quality. However, K application showed varied effects on tea yield and quality in soils with different available K levels. In terms of tea types, the yield and quality of black and green tea were enhanced under K application. The results of a mixed-effects model indicated that the main factors affecting tea quality were the amount of K fertilizer applied and the soil-available K content, whereas the variation in tea yield results mainly from the tea types. Therefore, to develop high-quality tea plantations and address the contradiction between low tea yield and high tea consumption, efforts should be made to enhance the soil-available K content by optimizing the amount of K applied on tea plantations.

全球茶叶（Camellia sinensisL.)产量一直在下降，尽管全球茶叶消费量和种植面积持续增加。鉴于茶园普遍缺乏土壤有效钾，施用钾 (K) 肥是提高茶叶产量和品质的常用方法。但钾肥施用对茶叶产量和品质的具体影响及其在不同钾肥施用量、土壤速效钾量和茶叶类型间的差异效应尚不清楚。本研究通过文献查阅获得了518份茶叶不施钾肥与施钾肥生产力的成对比较，并进行了分析。结果表明，施钾对茶叶产量和综合品质有显着正向影响，提高茶叶产量、氨基酸含量、茶多酚含量、水提取物和儿茶素含量分别为 7.83 %、7.84 %、26.79 %、1.57 % 和 6.47 %。此外，施钾量为 90–120 kg ha^-1使茶叶产量和质量最大化。然而，在不同速效钾水平的土壤中，施钾对茶叶产量和品质的影响各不相同。就茶叶类型而言，施钾提高了红茶和绿茶的产量和品质。混合效应模型结果表明，影响茶叶品质的主要因素是钾肥施用量和土壤速效钾含量，而茶叶产量的变化主要受茶叶类型的影响。因此，要发展优质茶园，解决茶叶产量低和茶叶消耗高的矛盾，应通过优化茶园施钾量，提高土壤速效钾含量。