Full Definitions: A regulation and control test device for preparing bio-oil by using fast thermal cracking of biomass, comprises a fluidized bed pyrolytic reactor, a cyclone separator, a coarse filter, a fixed bed thermal cracking reactor, a first multi-path sampling valve, a first gas chromatograph, a first-level condenser, a first oil storing tank, a high-temperature oil circulation groove, a second-level condenser, a second oil storing tank, a second low-temperature circulation groove, a third-level condenser, a third oil storing tank, a first low-temperature circulation groove, a second multi-path sampling valve, a second gas chromatograph, a suit of tail gas circulation device and a gas storing tank. The fluidized bed pyrolytic reactor is used for conducting pyrolytic reaction to the dried material to generate the carbon and the pyrolysis gas. The lower part of the reactor is provided with a feeding opening, the bottom thereof is provided with a gas inlet, and the upper side of a fast thermal cracking reactor is connected with the inlet of the cyclone separator. The cyclone separator is used for separating the carbon and the pyrolysis gas that is obtained via the pyrolytic reaction, and the outlet of the cyclone separator is connected with the inlet of the coarse filter. The coarse filter is used for filtering the pyrolysis gas obtained via the cyclone separation, and the outlet of the coarse filter is respectively connected with the fixed bed thermal cracking reactor and the inlet of the first multi-path sampling valve. The fixed bed thermal cracking reactor is used for conducting catalytic reaction to the pyrolysis gas, the upper side of the fixed bed thermal cracking reactor is formed with a hydrogen addition opening, and the lower part thereof is connected with the inlet of the first-level condenser. The first multi-path sampling valve is used for collecting the pyrolysis gas that is for gas chromatograph analysis before condensation, and the inlet and the outlet of the first multi-path sampling valve are respectively in parallel connection to the inlet and the outlet of the fixed bed thermal cracking reactor via a precise filter. The first gas chromatograph is used for online detecting and analyzing the thermal cracking gas in the fixed bed thermal cracking reactor at real time to provide the basic data to the regulation and control test of the bio-oil, and the first gas chromatograph is connected with the first multi-path sampling valve. The first-level condenser is used for conducting first-level condensation to the pyrolysis gas from the fixed bed thermal cracking reactor to obtain the bio-oil and the non-condensed gas, and the outlet at the lower part of the first-level condenser is connected with the inlet of the first oil storing tank. The first oil storing tank is used for storing the bio-oil from the first-level condenser, and the outlet of the first oil storing tank is connected with the inlet at the upper side of the second-level condenser. The high-temperature oil circulation groove is used for controlling the temperature of the condensing medium in the first-level condenser, and the high-temperature oil circulation groove is in parallel connection to the upper and the lower parts of the first-level condenser. The second-level condenser is used for conducting second-level condensation to the pyrolysis gas from the first-level condenser to obtain the bio-oil and the non-condensed gas, and the outlet at the lower part of the second-level condenser is connected with the inlet of the second oil storing tank. The second oil storing tank is used for storing the bio-oil from the second-level condenser, and the outlet of the second oil storing tank is connected with the inlet at the upper side of the third-level condenser. The second low-temperature circulation groove is used for controlling the temperature of the condensing medium in the second-level condenser, and the second low-temperature circulation groove is in parallel connection to the upper and the lower parts of the second-level condenser. The third-level condenser is used for conducting third-level condensation to the pyrolysis gas from the first-level condenser to obtain the bio-oil and the non-condensed gas, and the outlet at the lower part of the third-level condenser is connected with the inlet of the third oil storing tank. The third oil storing tank is used for storing the bio-oil from the third-level condenser, and the outlet of the third oil storing tank is connected with the gas storing tank. The first low-temperature circulation groove is used for controlling the temperature of the condensing medium in the third-level condenser, and the first low-temperature circulation groove is in parallel connection to the upper and the lower parts of the third-level condenser. The second multi-path sampling valve is used for collecting the pyrolysis gas that is for gas chromatograph analysis before condensation, and the inlet of the second multi-path sampling valve is respectively connected with the first oil storing tank, the second oil storing tank and the third oil storing tank via the precise filter. The second gas chromatograph is used for respectively online detecting and analyzing the thermal cracking gas in the first oil storing tank, the second oil storing tank and the third oil storing tank at real time to provide the basic data to the regulation and control test of the bio-oil, and the second gas chromatograph is connected with the second multi-path sampling valve. The tail gas circulation device comprises an attaching tank, two buffer tanks and an air compressor and is used for removing the impurity from the uncondensable gas and pressurizing the gas via the air compressor for circular gas loading in the fluidized bed pyrolytic reactor. The gas storing tank is used for storing the uncondensable gas for circular gas loading in the fluidized bed pyrolytic reactor, and the inlet of the gas storing tank is connected with the outlet of the third-level condenser.