To address the NASA need for a miniature pressure-leak sensor, Physical Optics Corporation (POC) proposes to develop a new Microelectromechanical System-based Internally Unpowered Sensor (MEMIUS). Fabrication of MEMIUS involves integration of a small MEMS piezoresistive sensor with proprietary miniature electronics and a novel wireless power transfer mechanism for device power-up and data read-out for a miniature footprint (2 cm x 2 cm x 1 cm, < 20 g weight). MEMIUS can be applied to both nonshielding and metal alloy shielding containers by utilizing inductive coupling with a small, efficient antenna, or a dual-band sensor antenna mounted on metal with a feed-through capacitor. MEMIUS represents an accurate pressure-leak sensor (~0.01 mbar) with no-battery on board electronics. It operates at low-temperatures with remote and efficient wireless power transfer capabilities at variable distances (1-10 m). These specifications are critical to the NASA search for an extremely rugged power efficient pressure sensor less than 5 cu. cm operating from -70 deg. C to +20 deg. C. The proposed MEMIUS thus solves the problems of weight, size, power efficiency, shielding, and electro-magnetic interference. The Phase I effort will demonstrate MEMIUS feasibility, and confirm its ruggedness and sensitivity. In Phase II POC will develop an advanced MEMIUS prototype.