The invention relates to a high-reliability permanent-magnet synchronous motor based on redundancy and fault-tolerant technology, which comprises a shell, two rotor assemblies, two stator assemblies, rotating shafts, bearings, insulating sleeves, a magnetic isolation plate and an end cover, wherein the two stator assemblies are coaxially connected in series; windings in each stator assembly are centralized single-layer windings which are isolated by teeth and embedded in fractional slots, and an electrical fault-tolerance structure is formed among the phase windings; due to the structural dimension design of the stator tooth slot, the induction of the phase winding of the motor is enhanced, thereby effectively inhibiting the short-circuit current; the two rotor assemblies are connected in series on the same shaft and are respectively arranged in the two stator assemblies; magnetic steel in each rotor assembly is of a thickness-unequal magnetic steel structure; the magnetic isolation plate is arranged between the adjacent two stator assemblies and is used for isolating electromagnetic interference between the stators and rotors at both ends; the two bearings are respectively arranged in bearing chambers of the shell and the end cover; and all the assemblies are packaged by the shell and the end cover together. The permanent-magnet synchronous motor provided by the invention has favorable physical isolation, magnetic isolation, thermal isolation and electrical isolation capabilities, and the reliability of the motor is greatly enhanced.