The characterization of a plasma plume is a key issue in laser ablation and deposition studies. The formation, composition and propagation of laser-produced plasmas used for pulsed laser deposition (PLD) of CN have been studied under film growth conditions. The plume was generated by focusing 1064 nm, 9 ns pulses from Nd:YAG laser on carbon target under nitrogen ambient. We investigated the different species, such as CII, CI, C2, NII and CN, in laser ablated CN plasma using optical emission spectroscopy. The spectral characteristics of the plasmas were measured to determine the plasma properties as gas pressure was changed from 10-5 to 90 mTorr. The intensities of molecular species did not depend on gas ambient whereas ion intensities did. The vibrational temperature shows dependence with gas pressure.