An expansion base has a body and an amplifier. The body has a front, an outer surface, a container, multiple through holes and a protruding strip. The through holes are formed through the outer surface of the body. The protruding strip is formed transversely on and protrudes from the outer surface at the front of the body. The amplifier is mounted in the container of the body and has at least one woofer mounted in the container adjacent to the through holes and two speaker mounted in the container. When the notebook is placed on the protruding strip, a space is formed between a surface and the notebook for improved user-comfort and heat dissipation. The notebook is connected to the amplifier for improved sound.