Boron based ducted rocket experimental system for ground simulation was established to study the boron combustion.Through heating the boron in a primary chamber by the combustion gas of the ethanol and oxygen, and using air react with boron in the secondary chamber, the working process under the condition of the flow field was simulated, and the similar condition for the real ducted rocket was obtained as following:the compositions of primary products are H₂, CO and boron particles, and in the secondary chamber, the total and static temperatures 1300-1400 K, total and static pressures 0.4-0.5 MPa and Mach number about 0.35.With the experimental system, the condensed products at different axial locations including the primary chamber, secondary chamber inlet, mixture region, combustion region, nozzle, were collected and analyzed by the Scanning Electron Microscope, X-ray diffraction and the energy dispersive X-ray spectroscopy.Results show that boron particles are grain during the reaction and its morphology changes a little.The boron is combusted mainly in the secondary chamber, and most in the combustion region, less in the region before the nozzle, and the lest in the mixture region.