A removable battery fixing assembly of an electric vehicle, comprising: a removable battery module comprising: a main body having a first side surface and a second side surface, wherein the first side surface and the second side surface is located adjacent to each other, and at least one guiding bar is disposed on the first side surface; and a fixing device installed in a vehicle body of an electric vehicle and characterised by comprising: a base; a driving part disposed on the base; a main transmission part connected with the driving part; a guiding part disposed on the base; a first stopping part pivotally coupled with the main transmission part; and a second stopping part pivotally coupled with the main transmission part through plural connection elements, wherein for installing the removable battery module in the vehicle body of the electric vehicle, the at least one guiding bar on the first side surface of the removable battery module is aligned with the guiding part and moved along the guiding part, wherein when the removable battery module is moved to a specified position, the main transmission part is driven by the driving part to be moved horizontally, so that the first stopping part is correspondingly rotated to urge against an end part of the guiding bar, wherein when the removable battery module is moved to the specified position, the second stopping part is correspondingly driven by the plural connection elements to lock the second side surface of the removable battery module. a removable battery module comprising: a main body having a first side surface and a second side surface, wherein the first side surface and the second side surface is located adjacent to each other, and at least one guiding bar is disposed on the first side surface; and a fixing device installed in a vehicle body of an electric vehicle and characterised by comprising: a base; a driving part disposed on the base; a main transmission part connected with the driving part; a guiding part disposed on the base; a first stopping part pivotally coupled with the main transmission part; and a second stopping part pivotally coupled with the main transmission part through plural connection elements, wherein for installing the removable battery module in the vehicle body of the electric vehicle, the at least one guiding bar on the first side surface of the removable battery module is aligned with the guiding part and moved along the guiding part, wherein when the removable battery module is moved to a specified position, the main transmission part is driven by the driving part to be moved horizontally, so that the first stopping part is correspondingly rotated to urge against an end part of the guiding bar, wherein when the removable battery module is moved to the specified position, the second stopping part is correspondingly driven by the plural connection elements to lock the second side surface of the removable battery module. a main body having a first side surface and a second side surface, wherein the first side surface and the second side surface is located adjacent to each other, and at least one guiding bar is disposed on the first side surface; and a fixing device installed in a vehicle body of an electric vehicle and characterised by comprising: a base; a driving part disposed on the base; a main transmission part connected with the driving part; a guiding part disposed on the base; a first stopping part pivotally coupled with the main transmission part; and a second stopping part pivotally coupled with the main transmission part through plural connection elements, wherein for installing the removable battery module in the vehicle body of the electric vehicle, the at least one guiding bar on the first side surface of the removable battery module is aligned with the guiding part and moved along the guiding part, wherein when the removable battery module is moved to a specified position, the main transmission part is driven by the driving part to be moved horizontally, so that the first stopping part is correspondingly rotated to urge against an end part of the guiding bar, wherein when the removable battery module is moved to the specified position, the second stopping part is correspondingly driven by the plural connection elements to lock the second side surface of the removable battery module. a base; a driving part disposed on the base; a main transmission part connected with the driving part; a guiding part disposed on the base; a first stopping part pivotally coupled with the main transmission part; and a second stopping part pivotally coupled with the main transmission part through plural connection elements, wherein for installing the removable battery module in the vehicle body of the electric vehicle, the at least one guiding bar on the first side surface of the removable battery module is aligned with the guiding part and moved along the guiding part, wherein when the removable battery module is moved to a specified position, the main transmission part is driven by the driving part to be moved horizontally, so that the first stopping part is correspondingly rotated to urge against an end part of the guiding bar, wherein when the removable battery module is moved to the specified position, the second stopping part is correspondingly driven by the plural connection elements to lock the second side surface of the removable battery module.