A coffee beans roaster includes a machine body. The machine includes a control unit. A roasting body is disposed in the machine body. The roasting body is a tube. The roasting body has an accommodation space therein. An electrothermal film is provided on an outer side of the roasting body. At two conductive electrodes are spaced and disposed on the electrothermal film. Thus, the heat generated by the electrothermal film can be adjusted by the control unit. Raw coffee beans are placed in the accommodation space of the roasting body. Through the electrothermal film, the raw coffee beans can be evenly heated in all directions to shorten the required time and to decrease the consumed power for roasting the raw coffee beans.
