Microelectromechanical systems (MEMS) devices have the advantages of small size, fast speed and low cost. MEMS-based miniature imaging probes have been developed for various optical ldquobiopsyrdquo imaging systems. These MEMS based optical imaging systems enable in vivo endoscopic optical ldquobiopsyrdquo, resulting in a paradigm shift of optical imaging of internal organs. In particular, MEMS based endoscopic optical coherence tomography (OCT) imaging, nonlinear optical imaging and confocal imaging will be discussed.