The levels of endogenous abscisic acid and total polyamine contents (putrescine and spermidine) were studied in two lichen species differing in desiccation tolerance. ABA and polyamine contents showed significant differences between air-dried and water-treated thalli of Pseudevernia furfuracea and Ramalina farinacea. The levels of putrescine (put) and spermidine (spd) in water-treated P. furfuracea thalli were found higher than in dry samples. The values for spd were almost threefold and for put almost 1.4-fold higher than in airdried samples. The levels of put and spd in water-treated R. farinacea were lower than in the air-dried samples. The lowest values for spd and put were almost 33-fold and 2.8-fold less, respectively. ABA contents of water-treated P. furfuracea and R. farinacea increased by 2.65% and 25.5% when compared with air-dried thallus.