Sirtuin 1 (SIRT1) is an evolutionarily conserved NAD(+)-dependent histone deacetylase that is necessary for caloric restriction-related lifespan extension. SIRT1, as an intracellular energy sensor, detects the concentration of intracellular NAD(+) and uses this information to adapt cellular energy output to cellular energy requirements. Previous studies on SIRT1 have confirmed its beneficial effects on cellular immunity to oxidative stress, reduction of fibrosis, suppression of inflammation, inhibition of apoptosis, regulation of metabolism, induction of autophagy and regulation of blood pressure. All of the above biological processes are involved in the pathogenesis of kidney diseases. Therefore, the activation of SIRT1 may become a therapeutic target to improve the clinical outcome of kidney diseases. In this review, we give an overview of SIRT1 and its molecular targets as well as SIRT1-modulated biological processes, with a particular focus on the role of SIRT1 in kidney diseases.