The invention provides a lithium slurry battery reactor. The lithium slurry battery reactor comprises positive pole reaction cavities, negative pole reaction cavities, unipolar diaphragms, negative pole current collectors, positive pole slurry and negative pole slurry, wherein each unipolar diaphragm is formed by an isolating layer and a positive pole porous current collector layer located on a single side of the isolating layer through close contacting, and a plurality of unipolar diaphragms are sequentially stacked in the sequence that isolation layers are placed oppositely; the distance between every two adjacent positive pole porous current collector layers is larger than 0 and preferably ranges from 1 mm to 10 mm, a gap between the every two adjacent positive pole porous current collector layers forms one positive pole reaction cavity, and the positive pole slurry is located in the positive pole reaction cavity; the distance between two adjacent isolating layers is larger than 0 and preferably ranges from 1 mm to 20 mm, and a gap between the adjacent isolating layers forms one negative pole reaction cavity; the negative pole current collectors are located in the negative pole reaction cavities, and the negative pole slurry is located between the negative pole current collectors and the isolating layers. With the adoption of the unipolar diaphragm structure, the problems of consumption of lithium ions and increasing of polarizing internal resistance due to deposition of metal lithium on the negative pole porous current collector layers in a bipolar diaphragm structure are solved.