An efficient protocol toward trisubstituted 3‐aminothiophenes has been developed through a [4+1] cycloaddition of enaminothiones and aldehydeN‐tosylhydrazones under transition‐metal‐free conditions. 3‐Aminothiophene derivatives as well as their chiral analogs were obtained in good to excellent yields. Direct interaction of the enaminothiones with the diazo compounds of α‐carbonyl or ester group‐functionalized