A coffee maker and a coffee preparation method thereof are disclosed, the coffee maker includes: a stator frame; a grinding chamber including a cavity is mounted on the stator frame, and a cover; the cavity is covered by the cover to enclose a grinding cavity, a bottom of the grinding cavity having a beverage outlet communicated with the beverage cavity; a grinding device including a grinding knife tackle disposed in the grinding cavity, and a motor disposed outside the grinding cavity to drive the grinding knife tackle to rotate; a coffee strainer, circularly arranged on a peripheral of the grinding knife tackle; a lower end of the coffee strainer abuts a bottom wall of the grinding cavity to separate the grinding cavity into a grinding bean cavity and a beverage cavity disposed on the periphery of the grinding bean cavity.