Abstract: The present invention discloses an imaging system and apparatus to obtain high-resolution low-noise intravital radionuclide imaging based on transparent window chamber. This imaging system is dedicated to preclinical research. It comprises a transparent window chamber, in particular a dorsal skin window chamber or a cranial chamber or an ear chamber or a spine cord chamber on a living animal, and a high-quality radionuclide imaging camera for the imaging of positron or electron. The apparatus is compatible with multimodality imaging, in particular magnetic resonance imaging (MRI), microscopy imaging including fluorescence microscopy, phosphorescence microscopy and two-photon microscopy.