Despite the indisputably essential role of zinc in the bilogical processes of photosynthetic autotrophs, its participation as prosthetic group of several enzymes like: Alcohol dehydrogenase, superoxide dismutase and carbonic anhidrase; its role as activator of others: dehydrogenases, aldolases, isomerases, transphosphorylases and RNA and DNA polymerases; and also the zinc-induced negative effects over hydrocarbon metabolism and protein synthesis; the functional role of zinc in the processes above mentioned is still unknown. The aim of this work has been to carry out a deep review over the more recent related knowledge. Besides, at the view of recent results obtained by several authors relating the zinc-deficiency-induced effects to light intensity received by the plant (Zhang y Wu, 1989) and its catalytic role in the kinase system acting in the phosphorylation of photosystem 2 proteins (Markwell et al. 1983, Baber, 1986); a work hypothesis is proposed: zinc plays a key role in the processes of photoinhibition and energy distribution into the photosynthetic apparatus.Peer reviewed