This study was conducted to determine the effect of adding magnesium on the chemical equilibrium of potassium. The study included five levels of magnesium, Mg₀, Mg₁, Mg₂, Mg₃, and Mg₄, and two levels of potassium, K₀ and K₁₀₀, in two soils of different textures. The results of the study showed that adding magnesium contributed to increasing soluble, exchangeable, and non-exchangeable potassium. And by 64.706, 105.882, 164.706, and 235.294% / 13.986, 29.680, 47.945, and 77.169% / 4.538, 8.372, 13.224, and 26.682% for the level Mg₁, Mg₂, Mg₃, and Mg₄ compared to Mg₀, respectively. The soil with a silt clay texture outperformed the soil Silt Clay Leom texture with percentages of 131.818, 15.074 and 8.254%, for dissolved, exchangeable and non-exchangeable potassium, respectively.