The present invention discloses a fixed-wing and electric multi-rotor composite aircraft, including an electric multi-rotor dynamic system and a main controller, the fixed-wing dynamic system and electric multi-rotor dynamic system are mutually independent structurally, the main controller includes the fixed-wing control system and an electric multi-rotor control system which is used for controlling the operation of the electric multi-rotor dynamic system, the main controller is also used for controlling the fixed-wing control system and the electric multi-rotor control system to operate independently or synergistically, the rotor rotating plane of the electric multi-rotor dynamic system is parallel to the airframe central shaft. The aircraft is able to shift between two flying modes freely, and takes off, lands and flies like a helicopter as well as a fixed-wing aircraft. A fixed-wing aircraft-helicopter mixed mode can also be used in the take-off, landing and flying process.