An ab-inito quartic force field of CCO- in its first excited state (A) over tilde (2)Sigma (+) is calculated from an aug-cc-VTZ basis set at CCSD(T) level of theory in order to compute the vibrational energy levels in the range 600-4800 cm(-1). A variational-perturbational approach is used to diagonalize the most important vibrational configurations constructed from harmonic vibrational wave functions. The result agree well with the most reliable experimental values studied in a neon matrix and predict as yet unobserved overtones bands in the vibrational structure of the (A) over tilde (2)Sigma (+) <--(X) over tilde (2)Pi spectrum of CCO-.