Results of X-ray diffraction studies on titanium aluminides stabilized by niobium, vanadium and molybdenum are reported to establish a phase relation in the Ti-25Al-10Nb-3V-1 Mo at % (Ti-25-10-3-1) alloy. It is shown that the composition of the phases probably deviated slightly from ideal stoichiometry Ti3Al for alpha(2) and Ti2AlNb for beta-type; its partial ordering in of the beta-phase type and the phase relation is 64% beta-type and 36% alpha(2) phase.