Abstract: A method for hydrothermal liquefaction of biomass, wherein the biomass supplied by pumps from a tank is provided to a reactor, in which the biomass is heated to obtain reactor products in the form of volatile, liquid and solid fractions, which are separated in a separator. The biomass supplied from the tank is pressurized in pumps, after which it is preliminarily heated in a heat exchanger. The preheated biomass is reheated in the reactor using microwave radiation. The temperature of the biomass inside the reactor is measured using temperature sensors and a controller, and based on the measurements of the temperature sensors and reflectometers, the power of radiation is adjusted to retain the biomass inside the reactor at the temperature of 374° C. to 400° C.