Aim. Selection, synthesis and biological properties of new compound play major role in creating original medicines. Methods and results. Therefore, to find new bioactive compounds 3-(alkylthio)-4-R-5-(thiophene-2-ylmethyl)-4H-1,2,4-triazoles, where R - methyl, ethyl, phenyl, have been synthesized, by alkylation reaction of 4-R-5-(thiophene-2-ylmethyl)-4H-1,2,4-triazole-3-thiols with 1-bromobutane, or 1-bromopentane, or 1-bromohexane, 1-bromoheptane, 1-bromooctane, 1-bromononane, 1-bromodekane in the n-butanol medium and their physical-chemical properties have been studied using modern physical-chemical methods of analysis, elemental analysis, IR spectroscopy, and their individuality using HPLC-MS. Conclusion. This suggests the possibility of further studying the biological effect of the synthesized compounds.