This article presents an analysis of the effect of the Ta‐doping position on the performance of SiN x ‐based resistive random access memories by comparing the electrical properties and conduction mechanisms of the devices. The electrical test results show that when the doping position moves down in the resistive switching (RS) layer, the resistance window of the device increases during the resistive switch process. However, the consistency of the parameter distribution decreases. The conduction mechanism of all Ta‐doped devices behaves as space charge limited current. According to the analysis of the RS model of the device, Ta in the RS layer connects and disconnects with the localized conductive filaments. The adjustment ability of the doping layer on the conductive channel and the reduction of the device stability when the doping position moves up are proposed. Proper Ta doping in the middle of the RS layer of the device allows the device to obtain a large resistance window with relatively stable characteristics.