A large-scale configuration interaction (CI) calculation using Program CIV3 of Hibbert is performed for the lowest 87 fine-structure levels of argon-like iron ions. We have calculated energy levels, oscillator strengths, and transition probabilities for all electric-dipole-allowed and intercombination transitions between the levels of 3s^2^3p^6^, 3s^2^3p^5^3d, 3s3p^6^3d, 3s^2^3p^5^4s, 3s^2^3p^5^4p, 3s^2^3p^5^4d, 3s3p^6^4s, 3s^2^3p^5^4f, 3s3p^6^4p, 3s^2^3p^5^5s, 3s^2^3p^5^5p, and 3s^2^3p^5^5d states of Fe ix in the LSJ coupling scheme. Lifetimes of the 3d levels are also determined. The calculations include the major correlation effects.