Summary 　Mitochondrial dysfunction has long been believed to be one of the major causes of the etiology of Parkinson’s disease （PD）. The gene products for autosomal recessive juvenile PD, parkin and PINK1, have now turned out to be directly involved in the autophagic elimination of the damaged mitochondria called mitophagy, which is thought to be required for the maintenance of a healthy mitochondrial population in the cells or tissues. PINK1/Parkin-mediated mitophagy involves the activation of the ubiquitin-proteasome and autophagy machineries, which could also be significant to other familial or sporadic forms of PD. The latest progress in PD study suggests that at least some forms of juvenile PD are characterized as a mitochondrial disorder beyond that of a neurodegenerative disorder although the validation of the disease relevance of mitophagy awaits further study.