A local glass transition temperature, T-g, around ionic aggregates in poly(ethylene-random-methacrylic acid) (E-MAA) ionomers neutralized with sodium has been studied by the combination of the position-selective spin probing and microwave power saturation method of electron spin resonance (ESR). 5DSA, 7DSA, 10DSA, and 12DSA spin probes based on stearic acid allowed us to determine the local T-g at different distances from the center of the ionic core (multiplet), whereas 10DND probe based on a nonadecane backbone reflected the T-g at the polyethylene (PE) matrix. The local T(g)s at the ionic multiplet itself and matrix region were determined to be 320 and 281 K, respectively, in the quenched E-MAA ionomer from the melt. Moreover, it was found that the region around the multiplets is dynamically restricted, and the thickness of the restricted region is ca. 10 angstrom. In the restricted region, the T-g gradually decreased with receding from the ionic multiplet. The thickness of the dynamically restricted region was in good agreement with the persistence length of the PE at the theta condition.