Ovo istraživanje obuhva ć a opažanja fenološke varijabilnosti od 28 provenijencija hrasta lužnjaka u bosansko­hercegovačkom pokusu provenijencija u Žepču. Pokus je baziran na slučajnom blok sustavu sa tri (3) ponavljanja, gdje je svaka provenijencija u svakom bloku predstavljena sa 36 biljaka, osim provenijencija Drvar, Mutnica, Zvornik i Vinac, koje su djelomično zastupljene u pokusu. Proces listanja praćen je tijekom 2012. i 2013. godine, od kraja ožujka do početka svibnja. Praćeno je pet (5) fenofaza listova koje su za hrast kitnjak razradili Derory i dr. (2006.). Analiza fenoloških faza pokazala je da postoje statistički značajne razlike između ispitivanih provenijencija. Razlike su potvrđene za početak, trajanje i završetak pojedinih fenoloških faza listanja između provenijencija, što ukazuje na genetsku varijabilnost između populacija i zavisnost fenoloških faza od vremenskih uvjeta. U ovom istraživanju nije bilo moguće napraviti razliku između provenijencija na osnovi najranijeg pojavljivanja faza. Provenijencija Bijeljina nešto ranije ulazi u fazu B u 2012. godini, dok u 2013. godini u fazu B ulazi u isto vrijeme kao i ostale provenijencije. Provenijencija Bosanska Dubica kasni s ulaskom u sve faze u obje godine, i kašnjenje u odnosu na ostale provenijencije u prosjeku iznosi 7-10 dana. S obzirom na lokaciju populacije Bosanska Dubica u planinskim uvjetima možemo pretpostaviti da se radi o kasnoj formi. Dobiveni rezultati već sada mogu biti korišteni u programu oplemenjivanja hrasta lužnjaka, kao i u očuvanju genetske varijabilnosti uz pomoć in situ i ex situ metoda. Dobivene rezultate treba koristiti za planiranje, repopulaciju i reintrodukciju hrasta lužnjaka u Bosni i Hercegovini. Ovo istraživanje treba nastaviti kako bi se dobila detaljnija slika o fenologiji hrasta lužnjaka i utvrdila eventualna prisutnost ranih i kasnih formi, uzimajući u obzir i učinke klimatoloških uvjeta. Our research of Phenological variability of 28 provenances of pedunculate oak in the Bosnian and Hercegovinian test of provenances in Žepce. The experiment is based in the accidentally random block system with three (3) repetitions, where each provenance in each block is represented by 36 plants (except provenances Drvar, Mutnica, Zvornik and Vinac, which are partially represented in the experiment). We have observed the process of leafing during years 2012 and 2013 and from the end of March to beginning of May. We followed five (5) phenofazes of leafing that were developed for sessile oak by Derory et al. (2006). The analysis of phenological phases has shown that there are statistically important differences between the investigated provenances. The differences have been confirmed for the start, duration and end of certain phenological phases during leafing in the provenances and it points to a genetic variability between the populations and the dependence of phenological phases on the weather conditions. In this research, based on the earliest appearance of the phases no differentiation between any of the provenances could be made. Bijeljina provenance entered phase B slightly earlier in 2012, while in 2013 it entered phase B at the same time as all the other groups. With the Bosanska Dubica provenance we observed lateness with all the phases in both years, however when compared to the other groups it averages a delay of 7-10 days and considering the location is in a mountainous conditions we can safely confirm that it is a matter of late form. It should be noted that the obtained results already have great possibility of implementation in breeding programme of pedunculate oak as well as in conservation of genetic variability with in situ and ex situ methods. The obtained results should be used for planning, repopulation and reintroduction of pedunculate oak in Bosnia and Hercegovina. This research should be done further and in more depth to obtain an even more details picture about the phenology of pedunculate oak and further research would help to establish the early and late forms while taking the weather and its effects into consideration.