The invention provides an amphiphilic block polymer based on polythiophene, and a preparation method and an electroactive micelle thereof. The polymer has a structure represented by formula I in the description. The amphiphilic block copolymer has a hydrophilic chain segment and a hydrophobic chain segment, and the electroactive micelle with a core-shell structure is obtained by regulating the proportions of the two chain segments. The amphiphilic block polymer is prepared by a one-step technology, the method is simple, and the row-coil type polythiophene diblock polymer with the core-shell structure is prepared for the first time by utilizing the electrostatic interaction between zwitterions and the dissolution characteristic of obvious difference between the zwitterions and polythiophene. The polythiophene and zwitterion block polymer is prepared based on ATRP initiation or Click coupling, and the amphiphilic block copolymer is prepared by adding a surfactant, and the electroactive micelle with the core-shell structure is prepared by using the pi-pi interaction between the zwitterions and the molecular chain segments of the conjugated polymer.