We consider the impact of the Heidelberg-Moscow claim for a detection of neutrino mass on the determination of the dark energy equation of state .
By combining the Heidelberg-Moscow result with the WMAP 3-years data and other cosmological datasets we constrain the equation of state to -1.67 < w < -1.05 at 95 \% c.l. , While future data are certainly needed for a confirmation of the controversial Heildelberg-Moscow claim , our result shows that future laboratory searches for neutrino masses may play a crucial role in the determination of the dark energy properties .