To provide a substrate dividing device with improved workability, in which a waste substrate to be taken out first is always positioned above after a printed board comprising a product substrate and the waste substrate coupled via a coupling is cut and divided.

The printed board 10 comprises the inner product substrate 11 and the outer waste substrate 12 coupled via the coupling 12a. A blade 24 of the substrate dividing device includes a barb 24a. As shown in Fig.(A), the blade 24 is pushed downward to cut the coupling 12a. Then, when the blade 24 is raised upward as shown in Fig.(B), the waste substrate 12 comes over the barb 24a of the blade 24 which has cut and is surely carried upward. After the cutting operation is completed, the waste substrate 12 is always positioned over (on an upper level of) the product substrate 11 as shown in Fig.(C). Therefore, when an operator removes the waste substrate 12 first, the product substrate 11 is not caught, and thus workability is improved.