We found that YGR146C of Saccharomyces cerevisiae encodes a functional homolog of Ecl1 that is involved in the chronological lifespan of Schizosaccharomyces pombe. When YGR146C is overexpressed, it extends the viability of wild-type S. cerevisiae cells after entry into the stationary phase, as in the case of Ecl1. We propose that Ecl1 family proteins are novel regulatory factors involved in chronological lifespan among yeasts.