Tropospheric ozone (O₃) pollution affects plant growth and indirectly plant potassium (K) uptake. Effects of elevated atmospheric ozone (p O₃) (50% higher than the ambient p O₃) on biomass and K uptake and distribution of five modern cultivars of wheat (Tritcium aestivum L. cv. Yangmai 15 (Y15), Yangmai 16 (Y16), Yannong 19 (YN19), Yangfumai 2 (YF2) and Jiaxing 002 (JX002) ) were investigated in fully open-air field in the Yangtze River delta. Results show that straw and grain responded more than root to elevated pO3. Y16, YN19 and JX002 decreased in yield, while Y15 and YF2 as not affected did not show any change. Under elevated p O₃, YF2 and JX002 decreased significantly in straw biomass, Y16 displayed a rising trend while Y15 and JX002 declining ones, indicating that the effect of elevated pO3 on accumulation and distribution of biomass of wheat varied with wheat cultivar. Simultaneously, YN19, Y15 and JX002 decreased significantly in total plant potassium uptake, while Y16 displayed a declining trend and YF2 a rising one. Elevated p O₃ also affected content and distribution of potassium in the plant and the effect varied with cultivar, too. Y16, YF2, YN19 and Y15 declined in K distribution ratio in root, which suggested that elevated p O₃ promoted potassium transfer from root to shoot, but JX002 increased, which meant elevated p O₃ retarded potassium transfer to shoot. Obviously, mechanism of the response to elevated p O₃ of wheat in absorption and distribution of potassium varied with cultivar. Elevated p O₃ significantly decreased the partial productivity of potassium fertilizer in Y16, YN19 and JX002 by 13.2% ~ 35.7%, but did not have such effect in Y15 and YF2, while it decreased K fertilizer utilization rate of JX002 and increased that of YF2, while it did not affect much that of Y15, Y16 and YN19. Therefore, it is advisable to take into account the factor of variety in evaluating O₃ effects on accumulation and distribution of biomass in wheat and potassium turnover in the plant–soil system.