This paper reports on thermal design of a micro linear tristable actuator with an integrated sensor platform. On the basis of theoretic analysis and previous works, a novel design for the set-up of the one-axis actuator is proposed, in which electromagnetic driving is used, and the actuator will be hold only with permanent magnet forces on the end. It consists of a slider carrying the movable structure to which the actuated component is connected mechanically and electrically. Springs with low stiffness in the plane of actuation but high stiffness in all other directions connect the movable structure to the slider frame. Conducting paths are situated on the springs to provide electrical connectivity on the movable structure. For the contacting, power supply and signal read out of the two micro sensors on the sensor chip, six conducting paths which were led over the mechanical spring are necessary. They carry a current up to 100 mA. In order to confirm the thermal stability by working under strong current on micro spring, a thermal analysis is made. Though the thermal FEA of microstructures is a very challenging, the essential convection coefficient is calculated with help of a CFD-Simulation of a 2D finite element. A 3D finite element modeling is presented in brief theoretical analysis, modeling and simulation of temperature distribution were done for the realized micro actuator. Simulations of temperature distribution in the realized actuator were done taking into account the thermal-mechanical deformation and stress by working under named current. A thermal measurement results to underlay the FEM model are shown. The obtained simulation and experimental results are graphically presented, compared and analyzed. At the end a conclusion was made and an aspect of the further work is presented.