Abstract Magnetic resonance imaging (MRI) is an indispensable non-invasive imaging technology for diagnostic medicine and basic research. Today’s MRI assumes single-photon excitation. More specifically, for each nuclear spin, a single photon accompanies the transition between energy states which creates MRI signal. This photon must resonate near the Larmor frequency. The goal of this project is to explore and develop an entire new class of MRI that utilizes multiphoton excitation. That is, instead of the usual single-photon resonance, the proposed technique can excite multiphoton resonances to generate signal for MRI by using multiple magnetic field frequencies, none of which are near the Larmor frequency. Only the total energy absorbed by a spin must correspond to the Larmor frequency. Multiphoton MRI is a radical new way to perform MRI. It introduces new flexibilities for excitation, encoding, contrast generation and reception. The project will explore and develop the essential hardware, pulse sequences, excitation and receiving techniques for clinically feasible multiphoton MRI. If successful, multiphoton MRI will pave the road for many new avenues to generate novel MRI images and benefit human health.