Using neutron diffraction, the cation distribution was determined in compositions of the titanomagnetite spinel series Fe3-xTixO4, 0≤x≤1, with x=0.6 and 1 at room temperature. The knowledge of the correct cation distribution of x=0.6 is necessary for predicting the change in magnetization of ozeanic pillow basalts with oxidation. For x=0.6, Ti ions occupy exclusively B-sites of the spinel lattice with the possible exception of a minute number occupying A-sites. In order to explain the diffraction pattern for x=1, the occupation of additional kinds of sites are discussed. The diffuse scattering in the background for both compounds shows broad peaks which are indicative of magnetic and chemical short range order.