We report here on the magnetic properties of compounds of composition Fe1−xCrxSbO4and Fe1−xGaxSbO4. The introduction of paramagnetic Cr3+and diamagnetic Ga3+into the rutile‐related iron antimonate lattice does not destroy the antisite atomic ordering which exists in iron antimonate of composition FeSbO4. The initial slope of the Curie temperature dependence onxis similar in both series, indicating that Fe3+‐Cr3+interactions are very small. The magnetic susceptibility measurements recorded from the compounds of composition Fe1−xCrxSbO4,x<0.4, and Fe0.9Ga0.1SbO4show them to behave as spin glasses at low temperatures. The inhibition of compounds of the type Fe1−xCrxSbO4,x>0.4, and Fe1−xGaxSbO4,x>0.1 to undergo a spin‐glass transition above 4.2 K is associated with a dilution effect.