Measurements have been made of the two-photon angular correlation from positrons annihilating in single-crystal molybdenum at room temperature. By means of a combination of conventional slits and Soller slits the number of annihilations for which the momentum lies along a line in the momentum distribution is obtained, and results are presented for the [ζ,ζ,0], [0,0,ζ, and [ζ,ζ,0.71] directions. Theoretical calculations of the angular correlation have been made based on the interpolation or pseudopotential scheme with s–d interaction included. The parameters of the interpolation scheme have been chosen so that an accurate representation is obtained of the APW band structure of Mattheiss. The positron wave function has been obtained in terms of 141 plane waves. The width of the calculated two-photon angular correlation is found to be much broader than the experimental width unless the relative s and d enhancement is considered.