Master of Philosophy (abbreviated as MPhil, M. Phil., M.Phil., M.Φ., M.Ph., M.Ph., M.Φ., or MA (Phil)) is a postgraduate academic master's degree awarded for a master's-level research project submitted as a thesis or "dissertation", followed by an oral defense or examination.

The MPhil is one of several research master's degrees, others including Master of Research (MRes), Master of Science by Research (MScR), and Master of Arts by Research (MAR).

The MPhil is typically a one- or two-year master's degree, depending on the university and the country in question. In some European countries, the MPhil is a three-year degree, and in some countries it is a two-year degree followed by a one-year research project.

The MPhil is a postgraduate research degree that is designed to prepare students for further academic research. It is a qualification that is recognized by universities and research institutions around the world.

The MPhil is also a valuable qualification for those who want to pursue a career in research and development (R&D), or in other fields that require a high level of research skills.