Compact optical systems are revolutionizing precision measurement with their miniaturized design and functionality. At the forefront of this revolution are metalenses, composed of sub-wavelength nanostructures. They have emerged as novel planar optical elements capable of replacing traditional bulky lenses in various compact optical applications. Meanwhile, single-pixel imaging provides a cost-effective, computation-based method for achieving exceptional imaging quality. In this work, a metalens is integrated with a single-pixel imaging architecture to project high-resolution Hadamard patterns onto microscopic samples, replacing conventional lens-to-detector configurations. The system can simultaneously retrieve high-quality amplitude and phase maps of micro targets, even under single-photon-level illumination conditions (1.7 photons/pixel/s). This breakthrough is ideal for biological samples, particularly in live cell imaging, where minimizing light exposure is critical to avoid photobleaching and phototoxicity. By delivering a cost-effective, compact, and high-performance solution, this system sets a new era for precision imaging in science and industry.