In the present paper we examined whether the liquid used in pitfall traps has any effect on the ground-dwelling insects, especially to ant communities in terms of species richness and abundance. Four liquids were tested in order to answer our hypothesis: brine, alcohol, glycol and vinegar. A total of 1136 insect specimens were collected during August 2010 in grassland habitat in Southern Transylvania. Coleoptera and Hymenoptera were the predominant taxa, as expected. Almost 70% of the specimens consisted of ants. 14 species were identified, most of them common, with the exception of Myrmica specioides Bondroit, 1918 which is a rare species. Although vinegar and brine yielded the highest number of ant specimens and individuals, Kruskal--Wallis test showed that there are no significant differences between the tested liquids. [ABSTRACT FROM AUTHOR]