Wireless multimedia sensor network (WMSN) is an energyconstrained network. Energy issue of WMSN directly affects the network lifetime. If the location of a destination node is known, routing requests (RREQs) can reduce forwarding range of the packet, and therefore unnecessary energy consumption. Location aided routing (LAR) thus appears. This paper proposes an improved LAR (ILAR) protocol to conduct crosslayer routing design by using congestion information of the media access control (MAC) layer. Simulation results show that ILAR possesses several features such as low overall latency, small routing overhead and high throughput, which are suitable for WMSN routing protocol.