In tokamak operations, the plasma disruptions with thermal quench and current quench (CQ) pose significant threats to device safety due to the heat loads and the generation of runaway electrons. Shattered pellet injection serves as an effective disruption mitigation technique, its impurity assimilation efficiency emerging as a critical factor for radiation control. This study investigates the effects of electron cyclotron resonance heating (ECRH) on the assimilation of Ne, D₂, and mixed impurities during fast shutdown on the J-TEXT tokamak. Experiments were conducted with pure Ne, pure D₂, and 90% Ne with 10% D₂ mixed pellets under plasma currents of 120–140 kA, with 300–350 kW ECRH on axis heating. The results show that ECRH can significantly enhance the assimilation rate of pure Ne impurities and effectively reduce their radiation asymmetry. For pure D₂ impurities injection, ECRH can only slow down the CQ rate; however, due to the inherent characteristics of D₂ and factors such as plasma E× B drift, it has no significant effect on the assimilation rate of D₂ impurities. For the 90% Ne with 10% D₂ mixed impurity injection, the effect of ECRH on the assimilation rate is comparable to that of pure Ne impurities. Additionally, the toroidal radiation asymmetry induced by the mixture itself is already low, so ECRH has no obvious additional impact on this aspect. This study confirms that on-axis ECRH has universality in optimizing the assimilation of Ne-containing impurity systems, and can specifically address the issues of pure Ne radiation asymmetry and pure D₂ CQ, providing key experimental basis for plasma disruption mitigation.