The invention discloses a non-gunpowder thermal expansion type miniature propeller and a preparation method thereof and belongs to the field of the microfluid propulsion technology and MEMSs. The propeller and the method are used for position holding, attitude control, orbit adjustment and the like of tiny satellites. An SOI (Silicon-On-Insulator) material is used in the propeller. Solid propellant is used for most propellers currently to obtain thrust, and the propelling amount cannot be accurately controlled. A pressure cavity of the miniature propeller is sealed between a buried oxide layer of an SOI silicon wafer and a glass sheet, the pressure of sealed gas in the pressure cavity can be adjusted according to requirements, and the effect that the propelling amount is accurately controlled can be achieved. A provided preparation technology is quite mature currently, batch machining is easy to achieve, and technical adjustment can be conducted according to the pressure required by the pressure cavity.