An　electrochemical　bromination　of　thiophenes　from　ammonium　bromide　is　developed　both　in　batch　and　continuous-flow　conditions.　Substituted　thiophenes　possessing　2-hydrogens　selectively　afford　a　series　of　2-bromothiophenes　while　2-substituted　benzothiophenes　generate　3-bromobenzo[b]thiophenes.　Based　on　the　cyclic　voltammetric　studies　and　literature,　a　bromine　cation　involved　mechanism　was　proposed.