Measurements of emission cross sections for the O+ -N2 collision system with the incident beam of 1-10 keV O+ in the ground O+(4S) and metastable O+(2D) and O+(2P) states are reported. The emission cross section induced by incident ions in the metastable state O+(2P) is much larger than that for the ground O+(4S) state. The emission cross section of N+2 ion for (0, 0), (0, 1), and (1, 2) bands system is measured and the ratio of intensities for these bands is established as 10: 3: 1. It is shown that the cross sections for the N+A - ions emissions in the dissociative charge exchange processes increase with the increase of the incident ion energy. The energy dependence of the emission cross section of the band (0, 0)λ = 391.4 nm of the first-negative band system of the N+2 and degree of linear polarization of emission in O+ -N2 collision are measured for the first time. An influence of an admixture of the ion metastable state on a degree of linear polarization is revealed. The mechanism of the processes realized during collisions of ground and metastable oxygen ions on molecular nitrogen have been established. It is demonstrated that for O+ -N2 collision system the degree of linear polarization by metastable O+(2P) ions is less compared to those that are in the ground O+(4S) state and the sign of emission of degree of linear polarization of excited molecular ions does not change.