A set of methylimidazolium-furanchalcone hybrids and 1-alkyl-3-methylimidazolium salts were tested in order to find their antimicrobial activity against five grampositive bacteria, two gram negative bacteria and three fungi. In the series of 1-alkyl-3-methylimidazolium salts, compounds 4 and 7 were the most active compoundsagainst S. mutans and F. oxysporum, respectively (MIC value of 3.0 and 6.7 mM, respectively). In addition, among the hybrid molecules, compound 10 exhibited thehighest activity against F. solani (MIC50 = 14.3 mM) followed by hybrid 11 (MIC50 = 14.5 mM), which was also the most active against S. aureus, S. mutans (MIC50= 14.6, 18.7 mM, respectively). The activity of these hybrids was even better with regard to the lead compounds (furanchalcone, methylimidazole or the mixture). Inthe structure-activity relationship there was observed higher bioactivity when the alkyl linker had eigth carbon atoms. This was then supported by the in silico studywhich displayed a strong relationship between the length of the alkyl chain on N and the biological activity. The results highlight the importance of these derivatives(1-alkyl-3-methylimidazolium salts) and hybrids (methylimidazolium-furanchalcone) as potential antimicrobial agents.