The formation of the Stark wings of hydrogen lines is considered on the basis of theoretical models of flares in type UV Cetus stars. It is shown that, under certain conditions (depending on the power of the beam of charged particles and their energy spectrum), very broad wings may be formed, extending 20 and more angstroms from the center of the line. Observations of such wings may provide valuable information concerning the energy spectra of the particles inducing the flare. © 1995 Plenum Publishing Corporation.