Abstract : A Two-Way Relay Channel (TWRC) in which duplex transmission between two users via a relay station is considered. A physical layer network coding strategy based on compress-and-forward relaying scheme for the TWRC is proposed. In the underlying coding strategy, we use nested lattices for Wyner-Ziv coding and decoding. The relay uses the weaker side information available at the receivers from the ﬁrst transmission phase to broadcast a common quantized version of its received signal. We characterize the achievable rate region of the presented scheme. Then we show that lattice codes can achieve random coding rates.