A simple separation method to obtain gibberellin standards is described.This includes isolation of the lactonic gibberellins GAg, GA4, GAy and GAgfrom Gibberella fujikuroi cultures by Chromatographie procedures and their structural characterization. Isolated gibberellins were derivatized as their methyl esters and identified by spectroscopic methods (IFVHNMR) as well as by co-chromatography with standards. 'H- NMR spectra of methyl esters of isolated fungal gibberellins allowed identification of GA, GA, GA7 and GAg by comparison with described spectra.