A bus bar assembly installed in a frame for fixing a plurality of stacked battery cells is provided. The bus bar assembly may include: a bus bar fixed to the frame; a flexible printed circuit board electrically connected to the bus bar and configured to sense the plurality of battery cells; and a connection terminal having a protrusion formed on one surface of the connection terminal, is the protrusion being configured to pass through the flexible printed circuit board so as to be electrically connected to the flexible printed circuit board, and the connection terminal configured to be electrically connected to the bus bar through the opposite surface of the one surface, the opposite surface being bonded to the bus bar.