A terminal block assembly includes a block housing, a surge protection device, a plurality of cable-receiving seats, a plurality of connector sets and a first fuse. The block housing defines an accommodating space that confines the surge protection device. The cable-receiving seats and the connector sets are mounted on the block housing. Each of the connector sets includes at least one first connector that is electrically connected to a light-emitting module of an outdoor lamp, and a second connector that extends into the accommodating space and that is electrically connected to the surge protection device. The first fuse is mounted to the block housing, and is electrically connected to the surge protection device.