Abstract: The present invention discloses a pyridinylcyanoguanidine derivative or a pharmaceutically acceptable salt thereof, which is useful as an NAMPT inhibitor, and useful as a potential agent for the chemotherapy of a variety of diseases associated with abnormal NAD+ expression. The pyridinylcyanoguanidine derivative has a parent structure including cyanoguanidine attached to piperazine or pyrrolidine by an intermediate aliphatic chain, to which a side arylformyl (or heterocyclylformyl) group and pyridinyl (or substituted pyridinyl) group are attached. This structure comes from the structural optimization of FK866, a high-efficiency NAMPT inhibitor. In the structure, the substituted formyl piperazine and substituted formyl pyrrolidine are the further optimizations on the basis of FK866, which strengthens the interaction with NAMPT.