Аннотация:Tth solid state equilibria in the ternary system at 550 C were established by means powder X-ray diffraction and energy-dispersive X-ray(EDX) spectroscopy on about 120 alloys which were synthesizedby arc-melting under argon atmosphere. At 550 C eleven ternary intermetallics were observed. Their crystallographic parameters will be presented in further publication. Twonovelintermetallics -Ce2Ru2Al and Ce2RuAl - belong to the new own structure type.