This　Letter　considers　the　robust　adaptive　tracking　control　problem　of　a　class　of　uncertain　chaotic　systems　with　time-varying　unknown　but　bounded　parameters.　A　novel　controller　is　designed　based　on　the　Lyapunov　stability　theory,　The　proposed　controller　ensures　that　the　states　of　the　controlled　chaotic　systems　globally　asymptotically　track　the　desired　bounded　trajectories.　Simulation　results　verify　the　effectiveness　of　the　proposed　controller.　(C)　2003　Elsevier　Science　B.V.　All　rights　reserved.