The invention relates to the technical field of automatic liquid level and object level measuring, more particularly to a four-wire system radio-frequency admittance liquid level and object level meter and a method thereof. The meter comprises an LC oscillatory circuit, a bridge circuit, a prime amplifying circuit, a detection synchronous circuit, a detection circuit, a signal amplifying circuit, an MSP430F147 single chip microcomputer, a 93C46EEPROM memory circuit, a liquid crystal display, an AD420 electric current output circuit, a keystroke input circuit, an electric relay output circuit and a continuous liquid level control automatic gearshift circuit. The signal of material level variation subjected to detection and integration is converted to a DC signal, transmitted to a CPU processor for processing, and then transmitted to the liquid crystal display for displaying. Comparing with the capacitance radio-frequency admittance and two-wire system radio-frequency admittance, the inventive product has great advantages in sales for chemical industry and sewage treatment industry, and the debugging and maintenance costs are reduced. The inventive product is irreplaceable in position measurement in high pressure high temperature and narrow space.