Taking symmetric full Navier-Stokes equations as governing equations, using two temperature and 11 species reacting air model, the hypersonic thermochemical nonequilibrium flow is simulated numerically. Then by using the "line-by-line" radiation model to compute radiation characteristics for the flowfield, the emission and absorption coefficients for 40000 wavelength points in 0.15～2μm are calculated. The radiation spectrum of air mixtrue and the main radiation specie NO in high enthalpy wind tunnel experiments is obtained. The calculation results indicate that vibration temperature exerts important effects on radiation.