Tailored for the WLAN,we propose a cross-layer resource allocation schemes based on multi-packet reception.Firstly,the condition of sharing the subchannel by more than one user is obtained.Secondly,the subchannel allocation scheme including "exclusive" and "share" modes are proposed.Finally,the expression of power and bit loading which meets the QoS requirement is derived.Analysis and simulation show that proposed scheme not only improves the system throughput efficiently but also reduces the average packet delay and has low computational complexity.