Radiofrequency resonator methods for level measurement of a dielectric liquid in a reservoir are considered. The methods are characterized by independency of measurement results on the value of dielectric permittivity of a liquid. The methods are realized via application of two sections of TEM (Transverse ElectroMagnetic) transmission lines. Both parallel conductors of a two-wire line section are installed vertically in a reservoir with a monitored liquid. This transmission line section is done hollow along all its length. Inside this cavity serving as an outer conductor of coaxial line section, a wire is coaxially installed serving as the inner conductor of this section of coaxial line. Under realization of one of these methods each of these sections contains a horizontal part at its lower end while under realization of the second method a horizontal part is contained at only one section of these two ones. These horizontal parts are filled in by a liquid fully along all their lengths and are drained under coming in of a liquid into a reservoir and its removal from a reservoir accordingly. The TEM transmission line sections are high frequency resonators. Their resonant frequencies of electromagnetic oscillations are measured. Level of a liquid in a reservoir is determined as a result of joint functional processing of these frequencies. This result is independent on the value of dielectric permittivity of a monitored liquid.