The yeast Saccharomyces cerevisiae is an excellent model for gaining insights into the molecular basis of human mitochondrial disorders, particularly those resulting from impaired mitochondrial metabolism. Yeast is a very well characterized system and most of our current knowledge about mitochondrial biogenesis in humans derives from yeast genetics and biochemistry. Systematic yeast genome-wide approaches have allowed for the identification of human disease genes. In addition, the functional characterization of a large number of yeast gene products resident in mitochondria has been instrumental for the later identification and characterization of their human orthologs. Here I will review the molecular and biochemical characterization of several mitochondrial diseases that have been ascribed to mutations in genes that were first found in yeast to be necessary for the assembly of the mitochondrial respiratory chain. The usefulness of yeast as a model system for human mitochondrial disorders is evaluated.