Through bioinformatics clustering analysis of shaker-type potassium channels in 13 kinds of plants (Arabidopsis thaliana, Orysa sativa, Zea mays, Soybean, Cucumis melo L., Daucus carota Linn., Vitis vinifera, Solanum tuberosum, Ammopiptanthus mongolicus, Medicago truncatula, Puccinellia tenuiflora, Cucumis sativus, and Populus tremula), Selected the C-terminal region reflect the characteristics of the C4 plants stomata open of Zea mays potassium ion absorption channel ZmK2.1, build the ZmK2.1 Arabidopsis thaliana overexpression of strains (OE#3, OE#5, OE#11), ZmK2.1-overexpressed Arabidopsis thaliana strain (OE#3, OE#5, OE#11) were constructed, and col-0 was used as control material to study potassium utilization efficiency of Arabidopsis thaliana ZmK2.1 overexpressed plants. Biomass, root length, K⁺ content andaccumulation, stomatal conductance, photosynthetic rate and transpiration rate were determined at low K (0.1 mol/L KCl), medium K (1 mol/L KCl) and high K (10 mol/L KCl) levels by solid medium and hydroponic culture. Compared with the control, the results show that root length, biomass, K⁺ content and accumulation of ZmK2.1-overexpressed Arabidopsis thaliana are significantly increased compared with the control under sufficient K⁺ content. Meanwhile, stomatal conductance, photosynthetic and transpiration rates of ZmK2.1-overexpressed Arabidopsis thaliana are significantly increased. The results of this study indicate that ZmK2.1 overexpression can significantly promote the growth and potassium utilization efficiency of Arabidopsis thaliana plants under the condition of sufficient potassium supply, which is closely related to the fact that ZmK2.1 can significantly increase stomatal conductance, and thus improve photosynthetic efficiency and transpiration rate.