The vortex chain is shown to be used as the source of terahertz radiation from the Josephson sandwich. The frequencies and power of the generated radiation are determined. The free uniform motion along the Oz axis with velocity v of the vortex Josephson chain in the superconducting sandwich geometry is determined by the equation for the phase difference of the condensate wave function on a tunnel interlayer. It is also found that the consumption of emission power for a time close to the ratio of the characteristic size of a single vortex to the chain velocity is small compared with the energy of the vortex structure, which is predetermined for the sandwich with not too thick electrodes. The number of harmonics that contribute to the spectral composition of the vortex chain emission in the specified magnetic field depends on the ratio between the chain period.