We report the results from magnetization and magneto-resistance measurements on polycrystalline Sr2Fe1-xCrxMoO6. A decrease in the saturation moment per f.u. is observed, which we attribute to site dilution for x <= 0.4 and anti-site disorder for x >= 0.6 along with a reduced Cr3+ saturation moment when compared with Fe3+. The magneto-resistance also decreases with increasing Cr substitution. This may be due to increased disorder leading to an increase in spin-scattering near the spin-tunnelling grain boundaries for x <= 0.4. There is no evidence for spin-tunnelling for x >= 0.6 and the magneto-resistance can be attributed to a reduction in intra-grain spin-scattering with increasing magnetic field. (c) 2007 Elsevier B.V. All rights reserved.