A glutathione S-transferase fused with the nuclear matrix targeting signal (GST-NMTS) of AML-1/CBF-alpha 2 has been crystallized by the vapor diffusion method using polyethylene glycol (PEG) as the precipitant. The NMTS is a 31-amino-acid signal peptide that can target the AML-1/CBF-alpha 2 protein to the nuclear matrix. The crystal belongs to tetragonal space group P4(3)2(1)2 with unit cell dimensions a = b = 93.4 Angstrom, c = 57.6 Angstrom. There is one GST-fusion protein per asymmetric unit. Crystals diffracted to at least 2.7 Angstrom and are appropriate for structure determination.