Based on the idea of integrated design, a drive-transmission integrated linear electromechanical actuator is developed. The actuator consists of a permanent magnet synchronous motor (PMSM), a ball-screw and shells. By using coaxial assemblage, the ball-screw is inserted into the hole of the hollow motor rotor and the nut of the ball-screw connects with the motor rotor. In order to restrict the ball-screw rotating relatively to the shell, splines machined respectively on ball-screw and the shell come into being a spline pair. A driver based on a DSP processor and IGBTs plus a position feedback resolver forms a precise servo system.