Abstract : Levitation is a fascinating way to compensate the action of gravity. Diamagnetism is the only physical phenomenon that allows a stable, static and passive levitation at room temperature. However, this magnetic effet is mostly insignificant at ordinary scales. Among the different means to improve the amplitude of this phenomenon, scale reduction is promishing. The present work contributes to the exploration of the possibilities and the potentialities of levitation in the microsystems. The reduction of size increases diamagnetic volume forces and strongly decreases absolute diamagnetic forces. These properties have been used for the conception and the fabrication of microsensors (accelerometer, inclinometer, force sensor) and microactuators (manipulation of microparticle by incline or by the use of a laser). These realisations are opening new fields for new perspectives and innovative functionnalities into the microworld.