Absorption spectra of CO2 and its isotopes in the 1mm region with spectral resolution 0,05 cm-1 using high sensitive intracavity laser spectrometers on the basis of Nd-glass and F2-: LiF color center lasers have been investigated. 12 rotation-vabration bands due to transitions to Fermi-diads 1003, 1113 and Fermi-triads 2003, 2113 were recorded. Spectroscopic parameters of upper vibration states of carbon dioxide were determined.