Department of Chemistry, St. John's College, Agra-282 002 Manuscript received 26 July 1982, accepted 30 May 1983 Different substituted thiosemicarbazides were synthesised by condensing 4-chloro­-2-methyl and 5-chloro-2-methylphenylmalonamic acid hydrazides with phenyl isothio­cyanate and substituted phenyl isothiocyanates. The compounds on cyclisation with sodium hydroxide yielded mercapto-1,2,4-triazoles. Some of them have been screened for their antibacterial and antifungal activity.