A bicycle rear sprocket assembly comprises a first sprocket. The first sprocket includes a first sprocket body, a plurality of first sprocket teeth, a bearing unit mounting section, and a first torque-transmitting structure. The plurality of first sprocket teeth extend radially outwardly from a first radially outer periphery of the first sprocket body with respect to a rotational center axis. The bearing unit mounting section is at least partly provided to a first radially inner periphery of the first sprocket body. The first torque-transmitting structure is configured to transmit pedaling torque to a second sprocket separately disposed adjacent to the first sprocket without another sprocket between the first sprocket and the second sprocket. The first torque-transmitting structure is provided to a first bicycle inbound facing surface and is a separate member from the second sprocket.