The present invention provides an inexpensive card connector assembly which is used for the connection with two cards having mutually different transmission speeds, which can maintain transmission characteristics, and which is therefore suitable for high-speed transmission. The card connector assembly comprises first and second card connectors that are stacked for the connection with two cards having mutually different transmission speeds, and transmission paths for connecting the first and second card connectors to a circuit board. The transmission paths comprise a plurality of first and second terminal parts that respectively extend from the first and second card connectors, and a rigid board to which the first and second terminal parts are connected. The first terminal parts which extend from the first card connector that is to be connected to a card with a relatively high transmission speed are such that a large portion of each adjacent first terminal part from the first card connector to the rigid board extends parallel in a single row.