Abstract: Mitochondria play a key role in cell metabolism. In addition to synthesizing ATP, they also participate in many physiological and pathological processes, including apoptosis, inflammation, oxidative stress, neuronal disease, tumor development, and aging. Most gene transcription of mitochondrial proteins occurs in the nucleus, so the biogenesis of mitochondria and the maintenance of mitochondrial homeostasis mainly depend on the expression of nuclear genes (nDNA) and mitochondria-nucleus interactions. Conversely, mitochondria can affect the expression of nuclear genes through nuclear transcription factors, a process called mitochondrial retrograde signaling. This review summarizes the research progress on mitochondria-nucleus retrograde signaling and its regulation, including the ways by which mitochondria regulate nuclear genes and affect biological processes, and discusses new strategies for the treatment of diseases that involve mitochondrial retrograde signaling in disease pathology.