A cat excreting Echinococcus multilocularis eggs was recently identified in Hokkaido, representing the first such observation in Japan. The cat was raised free-range and frequently ate rodents. Fecal egg examination revealed eggs of taeniids (EPG: 440) and Spirometra spp. (EPG: >1000). PCR targeting part of the mitochondrial cytochrome c oxidase subunit I gene of E. multilocularis was positive with DNA from 3 single isolated taeniid eggs, and sequence analysis of one amplicon confirmed E. multilocularis. The results indicated that the eggs of E. multilocularis distributed in Hokkaido can be excreted in cat feces, and suggested the necessity of further studies to clarify whether the eggs excreted in cat feces are infective and thus whether cats can serve as infectious source to humans in Japan.