© 2020 The Chemical Society of Japan Composite materials with polymers and inorganic fillers enable the preparation of a variety of functional polymer materials. In particular, composites with crystalline polymers and Ni microparticles (NiMPs) can be applied to thermoresponsive conductive materials which are called PTC (positive temperature coeffcient) materials. These materials are conductive around room temperature, and turn to insulators at high temperature. This phenomenon is induced by the volume expansion of the crystalline domains, therefore, the design of matrix polymers has been limited. Herein, we showed PTC phenomena by using polyacrylamide-based (co)polymers in lieu of crystalline polymers. Those materials showed PTC phenomena regarding conductivity probably owing to the hydrogen bonding, yet polyacrylamides are amorphous polymers.