The present invention relates generally to a bio-impedance analyser for bioelectrical impedance measurements. Accordingly, the bio-impedance analyser includes: a) a current generation unit, wherein the current generation unit includes a Voltage- Controlled Oscillator (VCO), pre-amplifier and Voltage-Controlled Current Source (VCCS); b) a voltage sensing unit or voltage detection unit, wherein the voltage sensing unit or voltage detection unit is able to measure voltage drop across a subject; c) a signal processing unit, wherein the signal processing unit includes at least one microcontroller for the calculation of bio impedance parameters; and d) output devices, wherein the output devices are able to display calculated results and/or to send connection.