Pollen ratios have been widely employed to infer vegetation and climate in arid and semi-arid regions globally. However, the reliability of pollen ratios in differentiating vegetation types and indicating climate characteristics has not been validated using vegetation data, as the relationship between modern pollen and vegetation is not directly equivalent. In this study, we examined six commonly used pollen ratios-Artemisia/Chenopodiaceae (A/ C), Artemisia/Cyperaceae (A/Cy), (Artemisia + Chenopodiaceae)/Poaceae ((A + C)/Po), Cyperaceae/Poaceae (Cy/Po), Poaceae/Asteraceae (Po/As), and the sum of relative abundance of xerophilous taxa (Chenopodiaceae, Ephedra, Nitraria, Tamaricaceae, and Zygophyllaceae, Sumxero)-using 1385 modern pollen samples and 2855 vegetation plot records from northern and western China. Vegetation plot data, in addition to modern pollen data, were used to validate the pollen ratios as well. The relationships between pollen ratios, vegetation, and climate were further analyzed numerically to assess the reliability of pollen ratios in distinguishing six vegetation types and in reflecting climatic characteristics. The results demonstrated that pollen-based and vegetation-based pollen ratios exhibited varying degrees of effectiveness in distinguishing vegetation types and reflecting precipitation condition. Pollen ratios derived from pollen assemblage and vegetation composition exhibited inconsistency in distinguishing most vegetation types and in representing precipitation. Certain pollen ratios demonstrated a stronger ability to distinguish vegetation types than to reflect precipitation. The pollen A/C ratio and Sumxero can be effectively used to differentiate temperate steppe from desert, as well as alpine desert from other alpine vegetation types, respectively. Most pollen ratios are not suitable for precipitation indication; only the A/C, A/Cy, (A + C)/Po and Sumxero exhibit limited sensitivity to precipitation within specific climatic ranges for the entire study region. However, when separating vegetation types, the pollen ratios and precipitation relationships are much weaker and even ineffective to some extent, than those for the whole region. The application of pollen ratios in distinguishing vegetation types and reflecting climatic characteristics should therefore be approached with caution and must take vegetation composition and the climatic context into account.