The cavity field spectra of two different atoms interacting with two-mode field s through Raman process are studied.The effects of relative coupling constant R=g2/g1 on the spectrum structure are discussed.It is found thatR pla ys a different role in the syectrum for vacuum,weak or strong initial field.Dege nerate spectrum structure appears usually forR=1 orR=0.A complicated a symmetric multipeak structure appears when R is between 0 and 1.When the f ield of upper frequency mode is vacuum,its spectrum is influenced sensitively by the field intensity of the other mode for fixed R.