Abstract: The load inertia and the torque interference of a electro-hydraulic servo systemapplying to a joint-type robot are changing in a wide range with the variations ofmotion state and position of the robot.It is in general difficult to give satisfactoryand uniform dynamic responses.In this paper a simple,effective and convergent algorithm of Model ReferencedAdaptive Control based upon Popov-Landau hyperstability method is presented forthis servo system with time-varying load inertia and strong interferences.The effec-tiveness of the control law and rapid adaptive control speed are verified by the si-mulation results.