Several recent experiments and demonstrations are carried out with very small satellites with mass in the range of 10Kg. One of the most important is the attitude control by means of microthruters which have to work in the range of 100÷1000μN. The aim of this work is the construction of a system for the measurement of the thrust produced by prototypes of micropropulsion system. A balance consisting of mainly two parts has been realised: • a suspension system of the moving part • a position transducer The suspension system is a flexural bearing and it behaves like a pendulum. In fact, two strips made of copper produce a restoring force, which counteracts the thrust generated by the propulsion system. The restoring force is due to two contributions: the elastic properties of the strips material and the gravity action on the moving mass. The position transducer is a laser system (LD 1605/Laser Micro-Epsilon) which allows to measure the displacement of the moving mass supported by the flexural bearing. The laser sensor is connected to a data acquisition board on a computer. The variation in the mean positions, obtained by a numerical filtering process, is proportional to the thrust.