To meet the requirement of mobile multimedia communication

the paper presents a new mobility model(MCM).MCM takes special requirements of mobile multimedia services into consideration

and is fit for real-world environment with obstacles.A routing algorithm

using MCM

is proposed for multimedia services in ad hoc networks.The algorithm is described in detail.This algorithm takes effects of obstacles into consideration

and is based on the basic routing protocols.By using standby nodes to provide alternate routing

it can not only obtain right route for transmission

but also avoid the link break.Compared with present routing algorithms

the algorithm is more adaptive to the transmission of mobile multimedia.