The magnetoresistance of bulk and epitaxial films of dopedn‐type yttrium iron garnet is reported for the first time. In (111) films a &Dgr;R/Rof −0.55% is observed as a saturating applied field H is rotated out of the (111) plane to the film normal. There is no observable change in &Dgr;R/Ras H is rotated in the (111) plane, with the current I in various directions in the (111) plane. This isotropy of &Dgr;R/Rin the (111) plane has not been observed in other ferromagnetic materials such as iron and nickel and is not understood as yet. The same isotropy in the (111) plane is also observed in bulk yttrium iron garnet. A possible use of this magnetoresistance for magnetoresistive detectors in magnetic bubble devices is discussed.