A glass panel unit includes a first panel, a second panel, a sealing portion in a frame shape, a plurality of pillars, and a gas adsorbent. The sealing portion in the frame shape hermetically bonds respective peripheral edges of the first panel and the second panel together so as to create an evacuated, hermetically sealed space between the first panel and the second panel. The plurality of pillars and the gas adsorbent are arranged in the hermetically sealed space. The gas adsorbent contains: a non-metallic getter material having a porous structure with the ability to adsorb gas molecules; and a metallic getter material having a metallic surface with the ability to adsorb gas molecules.