Embodiments of the disclosure provide a method and apparatus for resource sharing for D2D and cellular communications in a multicell network. The method comprises steps of: acquiring CSI on channels relating to D2D pair and a plurality of cellular users that potentially share resources with the D2D pair; and determining D2D transmit powers of the D2D pair on a plurality of frequency bands allocated to the plurality of cellular users and cellular transmit powers of the plurality of cellular users based on the CSI, to improve throughput of the multicell network.