The invention provides a three-dimensional printer and a three-dimensional printing method. The three-dimensional printer comprises multiple wire wheels, a printing head, a forming base, a movable motor component and a consumable supplying motor component, wherein each
wire wheel is provided with a kind of imaging material, the printing head is used for extruding the imaging material, the consumable supplying motor component comprises multiple motors, each motor is used for driving the corresponding imaging material to be transferred into the printing head, wherein a wire changing device is arranged between the consumable supplying motor component and the printing head, multiple
fiber material input ends and a
fiber output end are arranged on the wire changing device, the
fiber material output end is connected with the printing head, and the wire changing device is communicated with a guide hole between each fiber material input end and the fiber output end. The invention also provides the three-dimensional printing method applied to the three-dimensional printer. The guide holes are used for guiding fiber materials so as to improve imaging stability, the displacement of wires is avoided, and multi-color
volume rendering can also be realized through the single printing head, and the three-dimensional printer is simple in structure and low in cost.