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Summary Plants undergo several developmental transitions during their life cycle. In grapevine, a perennial woody fruit crop, the transition from vegetative/green‐to‐mature/woody growth involves transcriptomic reprogramming orchestrated by a small group of genes encoding regulators, but the underlying molecular mechanisms are not fully understood.We investigated the function of the transcriptional regulatorVviNAC33by generating and characterizing transgenic overexpressing grapevine lines and a chimeric repressor, and by exploring its putative targets through a DNA affinity purification sequencing (DAP‐seq) approach combined with transcriptomic data.We demonstrated that VviNAC33 induces leaf de‐greening, inhibits organ growth and directly activates the expression ofSTAY‐GREEN PROTEIN 1(SGR1), which is involved in Chl and photosystem degradation, andAUTOPHAGY 8f(ATG8f), which is involved in the maturation of autophagosomes. Furthermore, we show that VviNAC33 directly inhibitsAUXIN EFFLUX FACILITATOR PIN1,RopGEF1andATP SYNTHASE GAMMA CHAIN 1T(ATPC1), which are involved in photosystem II integrity and activity.Our results show that VviNAC33 plays a major role in terminating photosynthetic activity and organ growth as part of a regulatory network governing the vegetative‐to‐mature phase transition.