SEPARATOR FOR NON-AQUEOUS SECONDARY BATTERY AND NON-AQUEOUS SECONDARY BATTERY

Provided is a separator for a non-aqueous secondary battery containing a porous substrate; and a heat-resistant porous layer that is provided on one side or on both sides of the porous substrate, and that contains a polyvinylidene fluoride type resin A that is a polyvinylidene fluoride type resin containing a tetrafluoroethylene unit; a polyvinylidene fluoride type resin B that is a polyvinylidene fluoride type resin other than the polyvinylidene fluoride type resin A; and a filler, in which an average primary particle diameter of the filler contained in the heat-resistant porous layer is from 0.01 μm to 1.0 μm.