The electronic structures and optical conductivity (OC) spectrum of equiatomic FeAl alloy were calculated using a full-potential linearized-augmented-plane-wave method within a generalized-gradient approximation. The calculated OC spectrum does not agree well with the experimental one. Since the FeAl alloy is known to have a correlation-induced paramagnetic ground state, the so-called LDA + U method is applied to improve the agreement between the experimental and calculated spectra. If the LDA + U method is applied, the calculated equilibrium lattice constant is closer to the experimental one than the calculation without LDA + U. The inclusion of corrections for both the real and imaginary parts of the self-energy, as well as the LDA + U method, markedly improved the agreement between the experimental and calculated OC spectra. (c) 2005 Elsevier B.V. All rights reserved.