Abstract Experimental results and the analysis of a resistivity of La1−x(K, Ag)xMnO3 manganites are presented. The behavior of the resistivity ρ(T) in a wide temperature range and a phase transition region are described. For the description of ρ(T) near a phase transition temperature are used the representations of the percolation theory. A percolation threshold dependence on doping degree in La1−x(K, Ag)xMnO3 manganites is studied. In La1−xKxMnO3 system for samples with x ≤ 0.12, an infinite conductivity channel forms at temperatures below the Curie temperature, and with x > 0.12 of potassium concentrations it is appeared at T > TC.