A high-reflection attenuation light-interception apparatus having a measured optical plug (1) which is PC polished on its output terminal, a short ferrule (2) which has an internal graded index fiber (6) with a PC polished input terminal and diagonal polished output terminal, a receptacle (3) which directly connects the output terminal of the measured optical plug (1) and the input terminal of the short ferrule (2), a light-interception element which receives light propagated through the graded index fiber (6) in the short ferrule (2), and a light-interception element block which fixes in face to face relationship the output terminal of the short ferrule (2) and the receiving surface of the light-interception element (4).