Fundamentals of Theoretical Physics (in two volumes) is a logical continuation of the author's three-volume general course of physics. Everything possible has been done to avoid repeating what is contained in the three-volume course. The first volume is devoted to mechanics and electrodynamics, and the second volume to quantum mechanics. An appreciable difficulty appearing in studying theoretical physics is that quite often many mathematical topics have either never been studied by the reader or have been forgotten by him. To eliminate this difficulty, both volumes are furnished with detailed mathematical appendices. The book has been conceived as a training aid for students of non-theoretical specialities of higher educational institutions. It will also be helpful for physics instructors at higher schools, and for everyone interested in the subject but having no time to become acquainted with it using fundamental manuals.