A microactuator consisting of an inflatable elastic membrane based on the decomposition of a small mass of energetic material deposited on a silicon microstructured platform is presented for disposable lab-on-a-chip applications. The energetic-material-based actuator is characterized by its small size (< 0.25 mm 2× 100 µm), bio-compatibility and capability of generating sufficient overpressures (> 10 kPa) under low electrical power (< 100 mW) to eject a few nanolitres of fluid. This device has been fabricated using MEMS and microfluidic-compatible technology. The characterization of the actuation gave a pressurization of 13 kPa and a membrane deformation of 46 µm for an electrical initial power of 90 mW (6.5 V, 13.9 mA). All these characteristics make such a microactuator well adapted for microfluidic applications and especially for the ejection of fluids contained in micro-channels of a disposable lab-on-a-chip.