The even parity states of O16 are treated by taking into account the configuration of 2 ?ω excitation in the L-S coupling scheme and using the δ-interaction of the Wigner type. An approximate method is suggested and the 0+, 2+, 4+, states are solved. Rigorous solutions of the wave functions are obtained as well and compared with the approximate solutions. It is found that they are very close to each other. By using these approximate wave functions the monopole and E2 transition probabilities are calculated, and the results are in nice agreement with experiment, but do not show agreement for the energy level spacings.