A semiconductor device includes a first data transmitting/receiving circuit, a second data transmitting/receiving circuit, and a plurality of channels configured to couple the first and second data transmitting/receiving circuits. The first data transmitting/receiving circuit includes a Tx delay unit configured to transmit data to the plurality of channels, an Rx delay unit configured to receive data from the plurality of channels, and a de-skew control unit configured to control delay amounts of the Tx delay unit and the Rx delay unit according to phase information of reference clock signals received through the plurality of channels.